The purpose of this report is to summarize the current state of geologic knowledge concerning potential high-temperature geothermal development on the lands controlled by Hill Air Force Base (HAFB) at the Utah Testing and Training Range (UTTR) and the lands encompassed by the Dugway Proving Grounds (Dugway). This report is based on currently available published and publically available information. Most of the information presented here is purely geologic in nature. Therefore, the logistical issues (such as military exclusion areas, proximity to electrical infrastructure, and access) are additional considerations that are being addressed in a separate report that will be issued to HAFB by the SES corporation.

Geothermalresources may be classified into two types: high temperature, >150 C, suitable for electrical generation and low- to moderate-temperature, 20-150 C, suitable for direct use. To further the development of geothermalresources in California, a concentrated study of low-temperature and moderate-temperature geothermalresources has been conducted by the California Department of Conservation. As part of that study a map containing technical data on the geothermalresources of California is now available to help planners, local governments, etc. develop their local resources.

The GeothermalResource Assessment Program of the Hawaii Institute of Geophysics has conducted a series of geochemical and geophysical surveys throughout the State of Hawaii since February 1978. The results compiled during this study have been used to prepare a map of potentialgeothermalresource areas throughout the state. Approximately thirteen separate locations on three islands have been studied in detail. Of these, four areas are known to have direct evidence of a geothermal anomaly (Kilauea East Rift Zone, Kilauea Southwest Rift Zone, Kawaihae, and Olowalu-Ukumehame) and three others are strongly suspected of having at least a low-temperature resource (Hualalai west flank, Haleakala Southwest Rift, and Lualualei Valley). In the remainder of the areas surveyed, the data obtained either were contradictory or gave no evidence of a geothermalresource.

The widespread occurrence of geothermal manifestations in Nigeria is significant because the wide applicability and relative ease of exploitation of geothermal energy is of vital importance to an industrializing nation like Nigeria. There are two known geothermalresource areas (KGRAs) in Nigeria: the Ikogosi Warm Springs of Ondo State and the Wikki Warm Springs of Bauchi State. These surficial effusions result from the circulation of water to great depths through faults in the basement complex rocks of the area. Within sedimentary areas, high geothermal gradient trends are identified in the Lagos subbasin, the Okitipupa ridge, the Auchi-Agbede are of the Benin flank/hinge line, and the Abakaliki anticlinorium. The deeper Cretaceous and Tertiary sequences of the Niger delta are geopressured geothermal horizons. In the Benue foldbelt, extending from the Abalaliki anticlinorium to the Keana anticline and the Zambuk ridge, several magmatic intrusions emplaced during the Late Cretaceous line the axis of the Benue trough. Positive Bouguer gravity anomalies also parallel this trough and are interpreted to indicate shallow mantle. Parts of this belt and the Ikom, the Jos plateau, Bauchi plateau, and the Adamawa areas, experienced Cenozoic volcanism and magmatism.

This document highlights the applications of low-temperature geothermalresources and the potential for future uses as well as current Geothermal Technologies Program-funded projects related to low-temperature resources.

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The Hawaii GeothermalResources Assessment Program was initiated in 1978. The preliminary phase of this effort identified 20 PotentialGeothermalResource Areas (PGRA's) using available geological, geochemical and geophysical data. The second phase of the Assessment Program undertook a series of field studies, utilizing a variety of geothermal exploration techniques, in an effort to confirm the presence of thermal anomalies in the identified PGRA's and, if confirmed, to more completely characterize them. A total of 15 PGRA's on four of the five major islands in the Hawaiian chain were subject to at least a preliminary field analysis. The remaining five were not considered to have sufficient resourcepotential to warrant study under the personnel and budget constraints of the program.

This thesis provides an overview of geothermal power generation and the potential for geothermal energy utilization in China. Geothermal energy is thermal energy stored in the earth's crust and currently the only ubiquitously ...

This report presents an evaluation of the geothermalpotential of the Yuma, Arizona area. A description of the study area and the Salton Trough area is followed by a geothermal analysis of the area, a discussion of the economics of geothermal exploration and exploitation, and recommendations for further testing. It was concluded economic considerations do not favor geothermal development at this time. (ACR)

Favourability Map of British Columbia GeothermalResources by Sarah Kimball A THESIS SUBMITTED carbon economy stipulates that power supply must be from renewable and low emission sources. Geothermal energy offers significant benefits to British Columbia which hosts Canadas best geothermalresources

Representative well models have been constructed for eight major geothermal-resource areas. The models define representative times and costs associated with the individual operations that can be expected during drilling and completion of geothermal wells. The models were made for and have been used to evaluate the impacts of potential new technologies. The nature, construction, and validation of the models are presented.

The goal of the State Coupled Resource Assessment Program is to identify and evaluate geothermalresources in the state, particularly low-temperature potential. Eight tasks were identified and documented in this report as follows: bottom-hole temperature survey, heat flow and temperature gradient survey, data translation studies, gravity data, substate regions, information dissemination, state geothermal map, and reports. The project had three major products: (1) a map, GeothermalResources of Nebraska; (2) a significant amount of thermal data collected and documented within the state; and (3) a series of publications, presentations and meetings (documented as an Appendix).

Publish new thermal and drill data from the Dizie Valley Geothermal Field that affect evaluation of Basin and Range GeothermalResources in a very major and positive way. Completed new geophysical surveys of Dizie Valley including gravity and aeromagnetics and integrated the geophysical, seismic, geological and drilling data at Dizie Valley into local and regional geologic models. Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dizie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems. Documented a relation between natural heat loss for geothermal and electrical power production potential and determined heat flow for 27 different geothermal systems. Prepared data set for generation of a new geothermal map of North American including industry data totaling over 25,000 points in the US alone.

The environmental consequences of natural processes in a volcanic-fumerolic region and of geothermalresource development are presented. These include acute ecological effects, toxic gas emissions during non-eruptive periods, the HGP-A geothermal well as a site-specific model, and the geothermalresourcespotential of Hawaii. (MHR)

Field investigations conducted during 2011 support and expand the conclusion of the original Preliminary Report that discovery of a viable geothermal system is possible in the northwestern part of the Utah Testing and Training Range-South (UTTR-S), referred to henceforth as Focus Area 1. The investigations defined the southward extent of the Wendover graben into and near Focus Area 1, enhanced the understanding of subsurface conditions, and focused further geothermal exploration efforts towards the northwestern-most part of Focus Area 1. Specifically, the detailed gravity survey shows that the Wendover graben, first defined by Cook et al. (1964) for areas north of Interstate Highway 80, extends and deepens southwest-ward to the northwest corner of Focus Area 1. At its deepest point, the intersection with a northwest-trending graben there is favorable for enhanced permeability associated with intersecting faults. Processing and modeling of the gravity data collected during 2011 provide a good understanding of graben depth and distribution of faults bounding the graben and has focused the interest area of the study. Down-hole logging of temperatures in wells made available near the Intrepid, Inc., evaporation ponds, just north of Focus Area 1, provide a good understanding of the variability of thermal gradients in that area and corroborate the more extensive temperature data reported by Turk (1973) for the depth range of 300-500 m. Moderate temperature gradients in the northern part of the Intrepid area increase to much higher gradients and bottom-hole temperatures southeastward, towards graben-bounding faults, suggesting upwelling geothermal waters along those faults. Water sampling, analysis, and temperature measurements of Blue Lakes and Mosquito Willey's springs, on the western boundary of Focus Area 1, also show elevated temperatures along the graben-bounding fault system. In addition, water chemistry suggests origin of those waters in limestone rocks beneath the graben in areas with temperatures as high as 140 C (284 F). In conclusion, all of the field data collected during 2011 and documented in the Appendices of this report indicate that there is reasonable potential for a viable geothermalresource along faults that bound the Wendover graben. Prospects for a system capable of binary electrical generation are especially good, and the possibility of a flash steam system is also within reason. The next steps should focus on securing the necessary funding for detailed geophysical surveys and for drilling a set of temperature gradient wells to further evaluate the resource, and to focus deep exploration efforts in the most promising areas.

We describe the ongoing development of joint geophysical imaging methodologies for geothermal site characterization and demonstrate their potential in two regions: Krafla volcano and associated geothermal fields in ...

On May 16, 2006, the National Renewable Energy Laboratory (NREL) in Golden, Colorado hosted a geothermalresources workshop with experts from the geothermal community. The purpose of the workshop was to re-examine domestic geothermalresource estimates. The participating experts were organized into five working groups based on their primary area of expertise in the following types of geothermalresource or application: (1) Hydrothermal, (2) Deep Geothermal Systems, (3) Direct Use, (4) Geothermal Heat Pumps (GHPs), and (5) Co-Produced and Geopressured. The workshop found that the domestic geothermalresource is very large, with significant benefits.

Analysis of all geothermal aquifers in North Dakota and South Dakota indicates an accessible resource base of approximately 21.25 exajoules (10{sup 18} J = 1 exajoule, 10{sup 18} J{approximately}10{sup 15} Btu=1 quad) in North Dakota and approximately 12.25 exajoules in South Dakota. Resource temperatures range from 40{degree}C at depths of about 700 m to 150{degree}C at 4500 m. This resource assessment increases the identified accessible resource base by 31% over the previous assessments. These results imply that the total stratabound geothermalresource in conduction-dominated systems in the United States is two-to-three times greater than some current estimates. The large increase in the identified accessible resource base is primarily due to inclusion of all potentialgeothermal aquifers in the resource assessment and secondarily due to the expanded data base compiled in this study. These factors were interdependent in that the extensive data base provided the means for inclusion of all potentialgeothermal aquifers in the analysis. Previous assessments included only well-known aquifer systems and were limited by the amount of available data. 40 refs., 16 figs., 8 tabs.

Since 1978, the Division of Geology and Earth Resources of the Washington Department of Natural Resources has participated in the U.S. Department of Energy's (USDOE) State-Coupled GeothermalResource Program. Federal and state funds have been used to investigate and evaluate the potential for geothermalresources, on both a reconnaissance and area-specific level. Preliminary results and progress reports for the period up through mid-1980 have already been released as a Division Open File Report (Korosec, Schuster, and others, 1981). Preliminary results and progress summaries of work carried out from mid-1980 through the end of 1982 are presented in this report. Only one other summary report dealing with geothermalresource investigations in the state has been published. An Information Circular released by the Division (Schuster and others, 1978) compiled the geology, geochemistry, and heat flow drilling results from a project in the Indian Heaven area in the south Cascades. The previous progress report for the geothermal program (Korosec, Schuster, and others, 1981) included information on temperature gradients measured throughout the state, heat flow drilling in the southern Cascades, gravity surveys for the southern Cascades, thermal and mineral spring investigations, geologic mapping for the White Pass-Tumac Mountain area, and area specific studies for the Camas area of Clark County and Mount St. Helens. This work, along with some additional studies, led to the compilation of the GeothermalResources of Washington map (Korosec, Kaler, and others, 1981). The map is principally a nontechnical presentation based on all available geothermal information, presented as data points, tables, and text on a map with a scale of 1:500,000.

This report presents an overview of geothermalresource development for three-low temperature (i.e, <200{degree}F) sites in southern New Mexico: the Lower Animas Valley, the Las Cruces East Mesa, and Truth or Consequences. This report is intended to provide potentialgeothermal developers with detailed information on each site for planning and decision making purposes. Included in the overview for each site is both a full site characterization and an economic analysis of development costs associated with the construction and operation of both geothermal and fresh water systems at each of the three locations. The economic analysis focuses on providing utility services to a commercial greenhouse because greenhouse operations are among the most likely candidates for use of the resource base. 9 tabs., 8 figs.

Many, if not all, geothermalresources are subject to decreasing productivity manifested in the form of decreasing brine temperature, flow rate, or both during the life span of the associated power generation project. The impacts of resource productivity decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant conversion efficiency. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contracts in place may be subject to significant economic penalties if power generation falls below the default level specified. A potential solution to restoring the performance of a power plant operating from a declining productivity geothermalresource involves the use of solar thermal energy to restore the thermal input to the geothermal power plant. There are numerous technical merits associated with a renewable geothermal-solar hybrid plant in which the two heat sources share a common power block. The geo-solar hybrid plant could provide a better match to typical electrical power demand profiles than a stand-alone geothermal plant. The hybrid plant could also eliminate the stand-alone concentrated solar power plant thermal storage requirement for operation during times of low or no solar insolation. This paper identifies hybrid plant configurations and economic conditions for which solar thermal retrofit of a geothermal power plant could improve project economics. The net present value of the concentrated solar thermal retrofit of an air-cooled binary geothermal plant is presented as functions of both solar collector array cost and electricity sales price.

The work performed on hot dry rock (HDR) geothermalresource evaluation, site characterization, and geophysical exploration techniques is summarized. The work was done by region (Far West, Pacific Northwest, Southwest, Rocky Mountain States, Midcontinent, and Eastern) and limited to the conterminous US.

This report examines life cycle water consumption for various geothermal technologies to better understand factors that affect water consumption across the life cycle (e.g., power plant cooling, belowground fluid losses) and to assess the potential water challenges that future geothermal power generation projects may face. Previous reports in this series quantified the life cycle freshwater requirements of geothermal power-generating systems, explored operational and environmental concerns related to the geochemical composition of geothermal fluids, and assessed future water demand by geothermal power plants according to growth projections for the industry. This report seeks to extend those analyses by including EGS flash, both as part of the life cycle analysis and water resource assessment. A regional water resource assessment based upon the life cycle results is also presented. Finally, the legal framework of water with respect to geothermalresources in the states with active geothermal development is also analyzed.

This report examines life cycle water consumption for various geothermal technologies to better understand factors that affect water consumption across the life cycle (e.g., power plant cooling, belowground fluid losses) and to assess the potential water challenges that future geothermal power generation projects may face. Previous reports in this series quantified the life cycle freshwater requirements of geothermal power-generating systems, explored operational and environmental concerns related to the geochemical composition of geothermal fluids, and assessed future water demand by geothermal power plants according to growth projections for the industry. This report seeks to extend those analyses by including EGS flash, both as part of the life cycle analysis and water resource assessment. A regional water resource assessment based upon the life cycle results is also presented. Finally, the legal framework of water with respect to geothermalresources in the states with active geothermal development is also analyzed.

The potential of geothermal energy is estimated that can be used for direct heat applications and electrical power generation within the Bonneville Power Administration (BPA) marketing area. The BPA marketing area includes three principal states of Oregon, Washington, and Idaho and portions of California, Montana, Wyoming, Nevada, and Utah bordering on these three states. This area covers approximately 384,000 square miles and has an estimated population of 6,760,000. The total electrical geothermalpotential within this marketing area is 4077 MW/sub e/ from hydrothermal resources and 16,000 MW/sub e/ from igneous systems, whereas the total thermal (wellhead) potential is 16.15 x 10/sup 15/ Btu/y. Approximately 200 geothermalresource sites were initially identified within the BPA marketing area. This number was then reduced to about 100 sites thought to be the most promising for development by the year 2000. These 100 sites, due to load area overlap, were grouped into 53 composite sites; 21-3/4 within BPA preference customer areas and 31-1/4 within nonpreference customer areas. The geothermalresourcepotential was then estimated for high-temperature (> 302/sup 0/F = 150/sup 0/C), intermediate-temperature (194 to 302/sup 0/F = 90 to 150/sup 0/C), and low-temperature (< 194/sup 0/F = 90/sup 0/C) resources.

Matched pairs of known geothermal wells and springs with BLM proposed Wilderness Study Areas (WSAs) were identified by inspection of WSA and Geothermalresource maps for the states of Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming. A total of 3952 matches, for geothermal sites within 25 miles of a WSA, were identified. Of these, only 71 (1.8%) of the geothermal sites are within one mile of a WSA, and only an additional 100 (2.5%) are within one to three miles. Approximately three-fourths of the matches are at distances greater than ten miles. Only 12 of the geothermal sites within one mile of a WSA have surface temperatures reported above 50/sup 0/C. It thus appears that the geothermalpotential of WSAs overall is minimal, but that evaluation of geothermalresources should be considered in more detail for some areas prior to their designation as Wilderness.

Results are set forth for a continuing reconnaissance-level assessment of promising geothermal sites scattered through California. The studies involve acquisition of new data based upon field observations, compilation of data from published and unpublished sources, and evaluation of the data to identify areas suitable for more intensive area-specific studies. Forty sites were chosen for reporting on the basis of their relative potential for development as a significant resource. The name and location of each site is given, and after a brief synopsis, the geothermal features, chemistry, geology, and history of the site are reported. Three sites are recommended for more detailed study on the basis of potential for use by a large number of consumers, large volume of water, and the likelihood that the resource underlies a large area. (LEW)

A comprehensive analysis is presented of industrial markets potential for direct use of geothermal energy by a total of six industry sectors: food and kindred products; tobacco manufactures; textile mill products; lumber and wood products (except furniture); chemicals and allied products; and leather and leather products. A brief statement is presented regarding sectors of the economy and major manufacturing processes which can readily utilize direct geothermal energy. Previous studies on plant location determinants are summarized and appropriate empirical data provided on plant locations. Location determinants and potential for direct use of geothermalresources are presented. The data was gathered through interviews with 30 senior executives in the six sectors of economy selected for study. Probable locations of plants in geothermalresource areas and recommendations for geothermalresource marketing are presented. Appendix A presents factors which impact on industry location decisions. Appendix B presents industry executives interviewed during the course of this study. (MHR)

Preliminary studies of geothermal production potential for the North Dakota portion of the Williston Basin have been carried out. Reservoir data such as formation depth, subsurface temperatures, and water quality were reviewed for geothermal brine production predictions. This study, in addition, provides important information about net pay thickness, porosity, volume of geothermal water available, and productivity index for future geothermal direct-use development. Preliminary results show that the Inyan Kara Formation of the Dakota Group is the most favorable geothermalresource in terms of water quality and productivity. The Madison, Duperow, and Red River Formations are deeper formations but because of their low permeability and great depth, the potential flow rates from these three formations are considerably less than those of the Inyan Kara Formation. Also, poor water quality and low porosity will make those formations less favorable for geothermal direct-use development.

Geothermalresources that might provide substitute energy at any of 76 defense installations are identified and evaluated. The geologic characteristics and related economics of potentialgeothermalresources located at or near the 76 installations were estimated. The geologic assessment identified 18 installations with possible geothermalresources and 4 Atlantic Coastal Plain resource configurations that represented the alternatives available to East Coast bases. These 18 locations and 4 resource configurations, together with 2 possible resources at the White Sands Missile Range and a potentialresource at Kings Bay, Georgia, were examined to determine the relative economics of substituting potentialgeothermal energy for part or all of the existing oil, gas, and electrical energy usage. Four of the military installations - Mountain Home, Norton, Hawthorne, and Sierra - appear to be co-located with possible geothermalresources which, if present, might provide substitute energy at or below current market prices for oil. Six additional locations - Ellsworth, Luke, Williams, Bliss, Fallon, and Twentynine Palms - could become economically attractive under certain conditions. No geothermalresource was found to be economically competitive with natural gas at current controlled prices. Generation of electric power at the locations studied is estimated to be uneconomic at present.

Data compilation for the low-temperature program is being done by State Teams in two western states. Final products of the study include: a geothermal database, in hardcopy and as digital data (diskette) listing information on all known low- and moderate- temperature springs and wells in Nevada; a 1:1,000,000-scale map displaying these geothermal localities, and a bibliography of references on Nevada geothermalresources.

An assessment of the geothermalresources within a fifty-mile radius of the Yucca Mountain Project area was conducted to determine the potential for commercial development. The assessment includes collection, evaluation, and quantification of existing geological, geochemical, hydrological, and geophysical data within the Yucca Mountain area as they pertain to geothermal phenomena. Selected geologic, geochemical, and geophysical data were reduced to a set of common-scale digital maps using Geographic Information Systems (GIS) for systematic analysis and evaluation. Available data from the Yucca Mountain area were compared to similar data from developed and undeveloped geothermal areas in other parts of the Great Basin to assess the resourcepotential for future geothermal development at Yucca Mountain. This information will be used in the Yucca Mountain Site Characterization Project to determine the potential suitability of the site as a permanent underground repository for high-level nuclear waste.

Spurr volcano is a composite Quaternary cone of largely andesitic composition located on the west side of Cook Inlet about 80 miles west of Anchorage and about 40 miles from the Beluga electrical transmission line. Geologic mapping (Plate 1-1) shows that the present summit depression was produced by a Mt. St. Helens-type sector collapse, rather than by a caldera collapse. Geochronologic and previous tephrachronologic studies show that there has been an active magmatic system at Spurr volcano during the late Pleistocene-to-Holocene time interval that is of critical interest for geothermal energy resource assessment. Major effort was devoted to geochemical and geophysical surveys of the accessible area south of Mt. Spurr, in addition to geologic mapping and geochronologic studies. Many coincident mercury and helium anomalies were found, suggesting the presence of geothermal systems at depth. Extremely large electrical self-potential anomalies were also found, together with extensive zones of low resistivity discovered by our controlled-source audiomagnetotelluric survey. The juxtaposition of all of these different types of anomalies at certain areas on the south slope of Crater Peak indicates the presence of a geothermal system which should be accessible by drilling to about 2000 ft depth. It is also evident that there is a strong volcanic hazard to be evaluated in considering any development on the south side of Mt. Spurr. This hazardous situation may require angle drilling of production wells from safer areas and placement of power generation facilities at a considerable distance from hazardous areas.

The potential of geothermal energy for future electric power generation in New York State is evaluated using estimates of temperatures of geothermal reservoir rocks. Bottom hole temperatures from over 2000 oil and gas wells in the region were integrated into subsurface maps of the temperatures for specific geothermal reservoirs. The Theresa/Potsdam formation provides the best potential for extraction of high volumes of geothermal fluids. The evaluation of the Theresa/Potsdam geothermal reservoir in upstate New York suggests that an area 30 miles east of Elmira, New York has the highest temperatures in the reservoir rock. The Theresa/Potsdam reservoir rock should have temperatures about 136 {degrees}C and may have as much as 450 feet of porosity in excess of 8%. Estimates of the volumes of geothermal fluids that can be extracted are provided and environmental considerations for production from a geothermal well is discussed.

The Preston Geothermal prospect is located in northern Cache Valley approximately 8 kilometers north of the city of Preston, in southeast Idaho. The Cache Valley is a structural graben of the northern portion of the Basin and Range Province, just south of the border with the Eastern Snake River Plain (ESRP). This is a known geothermalresource area (KGRA) that was evaluated in the 1970's by the State of Idaho Department of Water Resources (IDWR) and by exploratory wells drilled by Sunedco Energy Development. The resource is poorly defined but current interpretations suggest that it is associated with the Cache Valley structural graben. Thermal waters moving upward along steeply dipping northwest trending basin and range faults emanate in numerous hot springs in the area. Springs reach temperatures as hot as 84░ C. Traditional geothermometry models estimated reservoir temperatures of approximately 125░ C in the 1970ĺs study. In January of 2014, interest was renewed in the areas when a water well drilled to 79 m (260 ft) yielded a bottom hole temperature of 104░ C (217░ F). The well was sampled in June of 2014 to investigate the chemical composition of the water for modeling geothermometry reservoir temperature. Traditional magnesium corrected Na-K-Ca geothermometry estimates this new well to be tapping water from a thermal reservoir of 227░ C (440░ F). Even without the application of improved predictive methods, the results indicate much higher temperatures present at much shallower depths than previously thought. This new data provides strong support for further investigation and sampling of wells and springs in the Northern Cache Valley, proposed for the summer of 2015. The results of the water will be analyzed utilizing a new multicomponent equilibrium geothermometry (MEG) tool called Reservoir Temperature Estimate (RTEst) to obtain an improved estimate of the reservoir temperature. The new data suggest that other KGRAs and overlooked areas may need to be investigated using improved geothermal exploration methods.

Previously conducted preliminary investigations within the deep Delaware and Val Verde sub-basins of the Permian Basin complex documented bottom hole temperatures from oil and gas wells that reach the 120-180C temperature range, and occasionally beyond. With large abundances of subsurface brine water, and known porosity and permeability, the deep carbonate strata of the region possess a good potential for future geothermal power development. This work was designed as a 3-year project to investigate a new, undeveloped geographic region for establishing geothermal energy production focused on electric power generation. Identifying optimum geologic and geographic sites for converting depleted deep gas wells and fields within a carbonate environment into geothermal energy extraction wells was part of the project goals. The importance of this work was to affect the three factors limiting the expansion of geothermal development: distribution, field size and accompanying resource availability, and cost. Historically, power production from geothermal energy has been relegated to shallow heat plumes near active volcanic or geyser activity, or in areas where volcanic rocks still retain heat from their formation. Thus geothermal development is spatially variable and site specific. Additionally, existing geothermal fields are only a few 10ĺs of square km in size, controlled by the extent of the heat plume and the availability of water for heat movement. This plume radiates heat both vertically as well as laterally into the enclosing country rock. Heat withdrawal at too rapid a rate eventually results in a decrease in electrical power generation as the thermal energy is ôminedö. The depletion rate of subsurface heat directly controls the lifetime of geothermal energy production. Finally, the cost of developing deep (greater than 4 km) reservoirs of geothermal energy is perceived as being too costly to justify corporate investment. Thus further development opportunities for geothermalresources have been hindered. To increase the effective regional implementation of geothermalresources as an energy source for power production requires meeting several objectives. These include: 1) Expand (oil and gas as well as geothermal) industry awareness of an untapped source of geothermal energy within deep permeable strata of sedimentary basins; 2) Identify and target specific geographic areas within sedimentary basins where deeper heat sources can be developed; 3) Increase future geothermal field size from 10 km2 to many 100ĺs km2 or greater; and 4) Increase the productive depth range for economic geothermal energy extraction below the current 4 km limit by converting deep depleted and abandoned gas wells and fields into geothermal energy extraction wells. The first year of the proposed 3-year resource assessment covered an eight county region within the Delaware and Val Verde Basins of West Texas. This project has developed databases in Excel spreadsheet form that list over 8,000 temperature-depth recordings. These recordings come from header information listed on electric well logs recordings from various shallow to deep wells that were drilled for oil and gas exploration and production. The temperature-depth data is uncorrected and thus provides the lower temperature that is be expected to be encountered within the formation associated with the temperature-depth recording. Numerous graphs were developed from the data, all of which suggest that a log-normal solution for the thermal gradient is more descriptive of the data than a linear solution. A discussion of these plots and equations are presented within the narrative. Data was acquired that enable the determination of brine salinity versus brine density with the Permian Basin. A discussion on possible limestone and dolostone thermal conductivity parameters is presented with the purpose of assisting in determining heat flow and reservoir heat content for energy extraction. Subsurface maps of temperature either at a constant depth or within a target geothermal reservoir are discusse

GeothermalResource Area 6 includes Lander and Eureka Counties. There are several different geothermalresources ranging in temperature from 70/sup 0/F to in excess of 400/sup 0/F within this two county area. Eleven of these resources are considered major and have been selected for evaluation in this area development plan. The various potential uses of the energy found at each of the 11 resource sites were determined after evaluating the study area's physical characteristics, land ownership and land use patterns, existing population and projected growth rates, and transportation facilities. These were then compared with the site specific resource characteristics. The uses considered were divided into five main categories: electrical generation, space heating, recreation, industrial process heat, and agriculture. Within two of these categories certain subdivisions were considered separately. The findings about each of the geothermal sites considered are summarized.

GeothermalResource Area 6 includes Lander and Eureka Counties. There are several different geothermalresources ranging in temperature from 70/sup 0/F to in excess of 400/sup 0/F within this two country area. Eleven of these resources are considered major and have been selected for evaluation in this Area Development Plan. The various potential uses of the energy found at each of the 11 resource sites were determined after evaluating the study area's physical characteristics, land ownership and land use patterns, existing population and projected growth rates, and transportation facilities. These were then compared with the site specific resource characteristics. The uses considered were divided into five main categories: electrical generation, space heating, recreation, industrial process heat, and agriculture. Within two of these categories certain subdivisions were considered separately. The findings about each of the 11 geothermal sites considered are summarized.

The following topics are discussed: the geological setting of the Hawaiian Islands, regional geology of the major islands, geohydrology of the Hawaiian Islands, Hawaiis' geothermalresources, and potential geological/hydrological problems associated with geothermal development. Souces of information on the geology of Hawaii are presented. (MHR)

New York State`s geothermal energy potential was evaluated based on a new resource assessment performed by the State University of New York at Buffalo (SUNY-Buffalo) and currently commercial technologies, many of which have become available since New York`s potential was last evaluated. General background on geothermal energy and technologies was provided. A life-cycle cost analysis was performed to evaluate the economics of using geothermal energy to generate electricity in upstate New York. A conventional rankine cycle, binary power system was selected for the economic evaluation, based on SUNY-Buffalo`s resource assessment. Binary power systems are the most technologically suitable for upstate New York`s resources and have the added advantage of being environmentally attractive. Many of the potential environmental impacts associated with geothermal energy are not an issue in binary systems because the geothermal fluids are contained in a closed-loop and used solely to heat a working fluid that is then used to generate the electricity Three power plant sizes were selected based on geologic data supplied by SUNY-Buffalo. The hypothetical power plants were designed as 5 MW modular units and sized at 5 MW, 10 MW and 15 MW. The life-cycle cost analysis suggested that geothermal electricity in upstate New York, using currently commercial technology, will probably cost between 14 and 18 cents per kilowatt-hour.

The US Department of Energy -- Geothermal Division (DOE/GD) recently sponsored the Low-Temperature GeothermalResources and Technology Transfer Program to bring the inventory of the nation`s low- and moderate-temperature geothermalresources up to date and to encourage development of the resources. The Oregon Institute of Technology, Geo-Heat Center (OIT/GHC) and the University of Utah Research Institute (UURI) established subcontracts and coordinated the project with the state resource teams from the western states that participated in the program. The California Department of Conservation, Division of Mines and Geology (DMG) entered into contract numbered 1092--023(R) with the OIT/GHC to provide the California data for the program. This report is submitted in fulfillment of that contract.

The purpose of this document is to report on the evaluation of geothermalresourcepotential on and around three different United States (U. S.) Air Force Bases (AFBs): Nellis AFB and Air Force Range (AFR) in the State of Nevada (see maps 1 and 5), Holloman AFB in the State of New Mexico (see map 2), and Mountain Home AFB in the State of Idaho (see map 3). All three sites are located in semi-arid parts of the western U. S. The U. S. Air Force, through its Air Combat Command (ACC) located at Langley AFB in the State of Virginia, asked the Federal Energy Management Program (FEMP) for technical assistance to conduct technical and feasibility evaluations for the potential to identify viable geothermalresources on or around three different AFBs. Idaho National Laboratory (INL) is supporting FEMP in providing technical assistance to a number of different Federal Agencies. For this report, the three different AFBs are considered one project because they all deal with potentialgeothermalresource evaluations. The three AFBs will be evaluated primarily for their opportunity to develop a geothermalresource of high enough quality grade (i.e., temperature, productivity, depth, etc.) to consider the possibility for generation of electricity through a power plant. Secondarily, if the resource for the three AFBs is found to be not sufficient enough for electricity generation, then they will be described in enough detail to allow the base energy managers to evaluate if the resource is suitable for direct heating or cooling. Site visits and meetings by INL personnel with the staff at each AFB were held in late FY-2009 and FY-2010. This report provides a technical evaluation of the opportunities and challenges for developing geothermalresources on and around the AFBs. An extensive amount of literature and geographic information was evaluated as a part of this assessment. Resourcepotential maps were developed for each of the AFBs.

Two aspects of the Texas and Louisiana Gulf Coast geopressured geothermalresource: (1) the technological requirements for well drilling, completion, and energy conversion, and, (2) the environmental impacts of resource exploitation are examined. The information comes from the literature on geopressured geothermal research and from interviews and discussions with experts. The technology characterization section emphasizes those areas in which uncertainty exists and in which further research and development is needed. The environmental assessment section discusses all anticipated environmental impacts and focuses on the two largest potential problems: (a) subsidence and (b) brine disposal.

Monte Carlo analysis has been applied in calculation of geothermalresource capacity based on volumetric method issued by Standar Nasional Indonesia (SNI). A deterministic formula is converted into a stochastic formula to take into account the nature of uncertainties in input parameters. The method yields a range of potential power probability stored beneath Lawu Mount geothermal area. For 10,000 iterations, the capacity of geothermalresources is in the range of 139.30-218.24 MWe with the most likely value is 177.77 MWe. The risk of resource capacity above 196.19 MWe is less than 10%. The power density of the prospect area covering 17 km{sup 2} is 9.41 MWe/km{sup 2} with probability 80%.

Geothermal studies were carried out on the island of Sao Miguel, Azores to characterize the nature of the resource, to estimate its magnitude, and to identify target areas toward which exploration and developmental drilling might be directed. The main geothermalresource areas are Furnas, Agua de Pau, and Sete Cidades, three Quaternary silicic volcanic centers characterized by summit calderas beneath which magmatic heat sources provide thermal energy to overlying hydrothermal convection systems. For each of the systems, the studies have defined the size of the system, the subsurface temperature, the thermodynamic state of fluid in the system, the chemical composition of the fluid, and permeable parts of the system. 8 figs. (ACR)

A preliminary appraisal of the direct heat geothermal energy resources of the Tennessee Valley region has been completed. This region includes Kentucky, Tennessee and parts of adjacent states. Intermediate and deep aquifers were selected for study. Basement and Top-of-Knox structure and temperature maps were compiled from oil and gas well data on file at various state geological survey offices. Results of this study indicate that the New Madrid seismic zone is the only area within the region that possesses potential for direct heat utilization. In other areas geothermal energy is either too deep for economical extraction or it will not be able to compete with other local energy resources. The only anomalously high temperature well outside the New Madrid seismic zone was located in the Rome Trough and near the central part of the eastern Kentucky coal basin. Geothermal energy in that region would face strong competition from coal, oil and natural gas.

Geopressured geothermal reservoirs are characterized by high temperatures and high pressures with correspondingly large quantities of dissolved methane. Due to these characteristics, the reservoirs provide two sources of energy: chemical energy from the recovered methane, and thermal energy from the recovered fluid at temperatures high enough to operate a binary power plant for electricity production. Formations with the greatest potential for recoverable energy are located in the gulf coastal region of Texas and Louisiana where significantly overpressured and hot formations are abundant. This study estimates the total recoverable onshore geopressured geothermalresource for identified sites in Texas and Louisiana. In this study a geopressured geothermalresource is defined as a brine reservoir with fluid temperature greater than 212 degrees F and a pressure gradient greater than 0.7 psi/ft.

requirements/kWh, and pounds brine/pound of steam to the turbine were ascertained. This was done over a range of downhole temperatures of from 350F to 475F. The studies illustrate the total interdependence of the geothermalresource and its associated power...

Separate abstracts were prepared for seven papers. Also included are a bibliography of geothermalresource information for the State of Washington, well temperature information and locations in the State of Washington, and a map of the geology of the White Pass-Tumac Mountain Area, Washington. (MHR)

This report describes the geothermalresources of the Southern Powder River Basin. The report contains a discussion of the hydrology as it relates to the movement of heated water, a description and interpretation of the thermal regime, and four maps: a generalized geological map, a structure contour map, a thermal gradient contour map, and a ground water temperature map. 10 figs. (ACR)

Geothermal and geopressure as well as geologic and geophysical data were studied to evaluate the potential for future development of geothermalresources underlying the Alabama Coastal Plain. Wire-line log data compiled and interpreted from more than 1300 oil and gas test wells included maximum recorded temperatures, mud weights, rock resistivities as related to geopressure, formation tops, fault locations, and depths to basement rock. The Alabama Coastal Plain area is underlain by a conduction dominated, deep sedimentary basin where geothermal gradients are low to moderate (1.0 to 1.8/sup 0/F/100 feet). In some areas of southwest Alabama, abnormally high temperatures are found in association with geopressured zones within the Haynesville Formation of Jurassic age; however, rocks of poor reservoir quality dominate this formation, with the exception of a 200-square-mile area centered in southernmost Clarke County where a porous and permeable sand unit is encased within massive salt deposits of the lower Haynesville. The results of a petrograhic study of the Smackover Formation, which underlies the Haynesville, indicate that this carbonate rock unit has sufficient porosity in some areas to be considered a potentialgeothermal reservoir. Future development of geothermalresources in south Alabama will be restricted to low or moderate temperature, non-electric applications, which constitute a significant potential energy source for applications in space heating and cooling and certain agricultural and industrial processes.

GRC Transactions, Vol. 31, 2007 391 Keywords Geothermal, energy resources, Great Basin, GPS, and will be incorporated in future models. Introduction Geothermal energy resources have long been associated of active crustal deformation and its spatial relationship to active geothermal systems in the northern

The Sonoma Valley area contains low-temperature geothermalresources (20 C {le} T {le} 90 C) having the potential for useful development. Sonoma Valley residents, local governments and institutions, private developers, and manufacturers may be able to utilize the geothermalresources as an alternate energy source. Historically, there have been at least six geothermal spring areas developed in the Sonoma Valley. Four of these (Boyes Hot Springs, Fetter's Hot Springs, Agua Caliente Springs, and the Sonoma State Hospital warm spring) lie on a linear trend extending northwestward from the City of Sonoma. Detailed geophysical surveys delineated a major fault trace along the east side of the Sonoma Valley in association with the historic geothermal areas. Other fault traces were also delineated revealing a general northwest-trending structural faulting fabric underlying the valley. Water wells located near the ''east side'' fault have relatively high boron concentrations. Geochemical evidence may suggest the ''east side'' fault presents a barrier to lateral fluid migration but is a conduit for ascending fluids. Fifteen of the twenty-nine geothermal wells or springs located from literature research or field surveys are located along or east of this major fault in a 10 km (6.2 miles) long, narrow zone. The highest recorded water temperature in the valley appears to be 62.7 C (145 F) at 137.2 meters (450 feet) in a well at Boyes Hot Springs. This is consistent with the geothermal reservoir temperature range of 52-77 C (126-171 F) indicated by geothermometry calculations performed on data from wells in the area. Interpretation of data indicates a low-temperature geothermal fluid upwelling or ''plume'', along the ''east side'' fault with subsequent migration into permeable aquifers predominantly within volcanic strata. It is quite likely other geothermal fluid ''plumes'' in association with faulting are present within the Sonoma Valley area. A 5.8 km{sup 2} geothermal zone, that parallels the fault trace, is delineated and is perhaps the most favorable area for further investigation and possible geothermal production.

Geothermal-relevant geosciences data from all 50 states (www.stategeothermaldata.org), federal agencies, national labs, and academic centers are being digitized and linked in a distributed online network via the U.S. Department of Energy-funded National Geothermal Data System (NGDS) to foster geothermal energy exploration and development through use of interactive online Ĺmashups,ĺdata integration, and applications. Emphasis is first to make as much information as possible accessible online, with a long range goal to make data interoperable through standardized services and interchange formats. An initial set of thirty geoscience data content models is in use or under development to define a standardized interchange format: aqueous chemistry, borehole temperature data, direct use feature, drill stem test, earthquake hypocenter, fault feature, geologic contact feature, geologic unit feature, thermal/hot spring description, metadata, quaternary fault, volcanic vent description, well header feature, borehole lithology log, crustal stress, gravity, heat flow/temperature gradient, permeability, and feature descriptions data like developed geothermal systems, geologic unit geothermal properties, permeability, production data, rock alteration description, rock chemistry, and thermal conductivity. Map services are also being developed for isopach maps, aquifer temperature maps, and several states are working on geothermalresource overview maps. Content models are developed preferentially from existing community use in order to encourage widespread adoption and promulgate minimum metadata quality standards. Geoscience data and maps from other NGDS participating institutions, or ônodesö (USGS, Southern Methodist University, Boise State University Geothermal Data Coalition) are being supplemented with extensive land management and land use resources from the Western Regional Partnership (15 federal agencies and 5 Western states) to provide access to a comprehensive, holistic set of data critical to geothermal energy development. As of September 2011, we have over 34,000 records registered in the system catalog, and 234,942 data resources online, along with scores of Web services to deliver integrated data to the desktop for free downloading or online use. The data exchange mechanism is built on the U.S. Geoscience Information Network (USGIN, http://usgin.org and http://lab.usgin.org) protocols and standards developed as a partnership of the Association of American State Geologists (AASG) and U.S. Geological Survey.

The geothermalresources of the Wind River Basin were investigated. Oil-well bottom-hole temperatures, thermal logs of wells, and heat flow data have been interpreted within a framework of geologic and hydrologic constraints. Basic thermal data, which includes the background thermal gradient and the highest recorded temperature and corresponding depth for each basin, is tabulated. Background heat flow in the Wind River Basin is generally insufficient to produce high conductive gradients. Only where hydrologic systems re-distribute heat through mass movement of water will high temperatures occur at shallow depths. Aquifers which may have the confinement and structural characteristics necessary to create such geothermal systems are the Lance/Fort Union, Mesa Verde, Frontier, Muddy, Cloverly, Sundance, Nugget, Park City, Tensleep, Amsden, Madison, Bighorn, and Flathead Formations. Of these the Tensleep Sandstone and Madison Limestone are the most attractive in terms of both productivity and water quality. Most of the identified geothermal anomalies in the Wind River Basin occur along complex structures in the southwest and south. The most attractive geothermal prospects identified are anomalous Areas 2 and 3 north of Lander, Sweetwater Station Springs west of Jeffrey City, and the thermal springs southwest of Dubois. Even in these areas, it is unlikely temperatures in excess of 130 to 150/sup 0/F can be developed. 16 refs., 7 figs., 7 tabs. (ACR)

James Manion, Warm Springs Power & Water Enterprises; David McClain, McClain & Associates

2007-05-17T23:59:59.000Z

In 2005 the Confederated Tribes of Warm Springs Tribal Council authorized an evaluation of the geothermal development potential on the Confederated Tribes of Warm Springs Reservation of Oregon. Warm Springs Power & Water Enterprises obtained a grant from the U.S. Department of Energy to conduct a geological assessment and development estimate. Warm Springs Power & Water Enterprises utilized a team of expert consultants to conduct the study and develop a strategic plan. The resource assessment work was completed in 2006 by GeothermEx Inc., a consulting company specializing in geothermalresource assessments worldwide. The GeothermEx report indicates there is a 90% probability that a commercial geothermalresource exists on tribal lands in the Mt. Jefferson area. The geothermalresource assessment and other cost, risk and constraints information has been incorporated into the strategic plan.

Geothermal energy is described in general terms with drawings illustrating the technology. A map of known and potentialgeothermalresources in the US is included. The 1992 program activities are described briefly. (MHR)

The Geopressured-Geothermal Program, now in its fifteenth year, is entering the transition period to commercial use. The industry cost-shared proposals to the consortium, represented in the presentations included in these proceedings, attest to the interest developing in the industrial community in utilizing the geopressured-geothermalresource. Sixty-five participants attended these sessions, two-thirds of whom represented industry. The areas represented by cost-shared proposals include (1) thermal enhanced oil recovery, (2) direct process use of thermal energy, e.g., aquaculture and agriculture, (3) conversion of thermal energy to electricity, (4) environment related technologies, e.g., use of supercritical processes, and (5) operational proposals, e.g., a field manual for scale inhibitors. It is hoped that from this array of potential use projects, some will persist and be successful in proving the viability of using the geopressured-geothermalresource. Such industrial use of an alternative and relatively clean energy resource will benefit our nation and its people.

The Geopressured-Geothermal Program, now in its fifteenth year, is entering the transition period to commercial use. The industry cost-shared proposals to the consortium, represented in the presentations included in these proceedings, attest to the interest developing in the industrial community in utilizing the geopressured-geothermalresource. Sixty-five participants attended these sessions, two-thirds of whom represented industry. The areas represented by cost-shared proposals include (1) thermal enhanced oil recovery, (2) direct process use of thermal energy, e.g., aquaculture and agriculture, (3) conversion of thermal energy to electricity, (4) environment related technologies, e.g., use of supercritical processes, and (5) operational proposals, e.g., a field manual for scale inhibitors. It is hoped that from this array of potential use projects, some will persist and be successful in proving the viability of using the geopressured-geothermalresource. Such industrial use of an alternative and relatively clean energy resource will benefit our nation and its people.

An extensive survey was conducted of the geothermalresourcepotential of Hot Springs Bay Valley on Akutan Island. A topographic base map was constructed, geologic mapping, geophysical and geochemical surveys were conducted, and the thermal waters and fumarolic gases were analyzed for major and minor element species and stable isotope composition. (ACR)

A demonstration high rate aquaculture production system utilizing a cascaded geothermalresource was designed, constructed and operated to fulfill the objectives of this project. Analysis of the energy and water balances for the system indicated that the addition of an Aquaculture Facility expanded the use of the existing resource. This expanded use in no way affected the up- stream processes. Analysis of the system`s energy and water requirements indicated that the present resource was under-utilized and could be expanded. Energy requirements appeared more limiting than water use, but the existing system could be expanded to a culture volume of 72,000 gal. This system would have a potential production capacity of 93,600 lb/yr with a potential market value of $280,00/yr. Based on the results of this study, the heat remaining in the geothermal fluid from one square foot of operating greenhouse is sufficient to support six gallons of culture water for a high density aquaculture facility. Thus, the over 1.5M ft{sup 2} of existing greenhouse space in New Mexico, has the potential to create an aquaculture industry of nearly 9M gal. This translates to an annual production potential of 11.7M lb with a market value of $35.lM.

In early 1978 financial assistance was granted for a project to utilize geothermal energy at Ore-Ida Foods, Inc.'s food processing plant in Ontario, Oregon. Specifically, the project included exploring, testing, and developing the potentialgeothermalresource; retrofitting the existing gas/oil-fired steam system; utilizing the geothermalresource for food processing, space heating, and hot potable water; and injecting the spent geothermal water back into a disposal well. Based on preliminary investigations which indicated the presence of a local geothermalresource, drilling began in August 1979. Although the anticipated resource temperature of 380/sup 0/F was reached at total well depth (10,054 feet), adequate flow to meet processing requirements could not be obtained. Subsequent well testing and stimulation techniques also failed to produce the necessary flow, and the project was eventually abandoned. However, throughout the duration of the project, all activities were carefully monitored and recorded to ensure the program's value for future evaluation. This report presents a culmination of data collected during the Ore-Ida project.

Geothermalresource data, the Roosevelt-Custer Region development plan, and energy, economic, and institutional considerations are presented. Environmental considerations and water availability are discussed. (MHR)

With financial support from the U.S. Department of Energy (DOE), Layman Energy Associates, Inc. (LEA) has completed a program of geothermal exploration at the Truckhaven area in Imperial County, California. The exploratory work conducted by LEA included the following activities: compilation of public domain resource data (wells, seismic data, geologic maps); detailed field geologic mapping at the project site; acquisition and interpretation of remote sensing imagery such as aerial and satellite photographs; acquisition, quality control and interpretation of gravity data; and acquisition, quality control and interpretation of resistivity data using state of the art magnetotelluric (MT) methods. The results of this exploratory program have allowed LEA to develop a structural and hydrologic interpretation of the Truckhaven geothermalresource which can be used to guide subsequent exploratory drilling and resource development. Of primary significance, is the identification of an 8 kilometer-long, WNW-trending zone of low resistivity associated with geothermal activity in nearby wells. The long axis of this low resistivity zone is inferred to mark a zone of faulting which likely provides the primary control on the distribution of geothermalresources in the Truckhaven area. Abundant cross-faults cutting the main WNW-trending zone in its western half may indicate elevated fracture permeability in this region, possibly associated with thermal upwelling and higher resource temperatures. Regional groundwater flow is inferred to push thermal fluids from west to east along the trend of the main low resistivity zone, with resource temperatures likely declining from west to east away from the inferred upwelling zone. Resistivity mapping and well data have also shown that within the WNW-trending low resistivity zone, the thickness of the Plio-Pleistocene sedimentary section above granite basement ranges from 1,900ľ2,600 meters. Well data indicates the lower part of this sedimentary section is sand-rich, suggesting good potential for a sediment-hosted geothermal reservoir in porous sands, similar to other fields in the region such as Heber and East Mesa. Sand porosity may remain higher in the eastern portion of the low resistivity zone. This is based on its location hydrologically downstream of the probable area of thermal upwelling, intense fracture development, and associated pore-filling hydrothermal mineral deposition to the west.

For the past several years geothermal exploratory work has been conducted in northern Nevada. In conjunction with that effort a proposed 55-MW steam geothermal power plant was considered for initial installation in one of the fields being developed...

The U.S. Air Force is facing a number of challenges as it moves into the future, one of the biggest being how to provide safe and secure energy to support base operations. A team of scientists and engineers met at Mountain Home Air Force Base in early 2011 near Boise, Idaho, to discuss the possibility of exploring for geothermalresources under the base. The team identified that there was a reasonable potential for geothermalresources based on data from an existing well. In addition, a regional gravity map helped identify several possible locations for drilling a new well. The team identified several possible sources of funding for this wellŚthe most logical being to use U.S. Department of Energy funds to drill the upper half of the well and U.S. Air Force funds to drill the bottom half of the well. The well was designed as a slimhole well in accordance with State of Idaho Department of Water Resources rules and regulations. Drilling operations commenced at the Mountain Home site in July of 2011 and were completed in January of 2012. Temperatures increased gradually, especially below a depth of 2000 ft. Temperatures increased more rapidly below a depth of 5500 ft. The bottom of the well is at 5976 ft, where a temperature of about 140░C was recorded. The well flowed artesian from a depth below 5600 ft, until it was plugged off with drilling mud. Core samples were collected from the well and are being analyzed to help understand permeability at depth. Additional tests using a televiewer system will be run to evaluate orientation and directions at fractures, especially in the production zone. A final report on the well exploitation will be forthcoming later this year. The Air Force will use it to evaluate the geothermalresourcepotential for future private development options at Mountain Home Air Force Base. In conclusion, Recommendation for follow-up efforts include the following:

This report is a limited review of and presents comments on the geothermalresource exploration program of Kyushu Electric Power Company (KEPCO). This program is for developing geothermalresources to generate electric power on Kyushu Island, Japan. Many organizations in Japan and in particular Kyushu Electric Power Co., Inc. are actively exploring for and developing geothermalresources on Kyushu Island. KEPCO has already demonstrated an ability and expertise to explore for geothermalresources by their successful exploration and subsequent development of several fields (Hatchobaru and Otake) on the island of Kyushu for electric power generation. The review and comments are made relative to the geothermalresource aspects of Kyushu Electric Power Company's geothermal exploration program, and within the time, budget, and scope of the Rogers Engineering's effort under the existing contract. Rogers and its consultants have had a wide variety of geothermal exploration experience and have used such experience in the analysis of what has been presented by KEPCO. The remainder of the introduction section develops general knowledge concerning geothermal power development with particular emphasis on the resource exploration. The data received section describes the information available to perform the project work. There are no interpretative parts to the data received section. The philosophy section relates our understanding of the KEPCO thinking and conditions surrounding current geothermalresource development in Japan. The survey and methods sections presents three important items about each study KEPCO has performed in the resource exploration program. These three aspects are: what should be obtained from the method, what data was obtained and presented, and what is a review and analysis of where the KEPCO exploration program is currently in terms of progress and successful location of reservoirs. The final section presents recommendations on the many aspects of the resource exploration for geothermal power development.

Use of geothermal energy (heat from the earth) has a small impact on the environmental relative to other energy sources; avoiding the problems of acid rain and greenhouse emissions. Geothermalresources have been utilized for centuries. US electrical generation began at The Geysers, California in 1960 and is now about 2300 MW. The direct use of geothermal heat for industrial processes and space conditioning in the US is about 1700 MW of thermal energy. Electrical production occurs in the western US and direct uses are found throughout the US. Typical geothermal power plants produce less than 5% of the CO{sub 2} released by fossil plants. Geothermal plants can now be configured so that no gaseous emissions are released. Sulfurous gases are effectively removed by existing scrubber technology. Potentially hazardous elements produced in geothermal brines are injected back into the producing reservoir. Land use for geothermal wells, pipelines, and power plants is small compared to land use for other extractive energy sources like oil, gas, coal, and nuclear. Per megawatt produced, geothermal uses less than one eighth the land that is used by a typical coal mine and power plant system. Geothermal development sites often co-exist with agricultural land uses like crop production or grazing.

Temperature gradient map and published heat flow data indicate a possible potential for a geothermalresource in western and central New York State. A new analysis of bottom-hole temperature data for New York State confirms the existence of three positive gradient anomalies: the East Aurora, Cayuga, and Elmira anomalies, with gradients as high as 32/sup 0/C/km, 36/sup 0/C/km, and 36/sup 0/C/km, respectively. Ground waters from two of these anomalies are enriched in silica relative to surrounding areas. Heat flows based on silica geothermometry are 50 to 70 mWm/sup -2/ for the anomalies and 41.4 mWm/sup -2/ for bordering regional flux. A correlation between Bouguer gravity anomalies and the temperature gradient map suggests that the geothermal anomalies may occur above radioactive granites in the basement.

Geothermal research at the National Renewable Energy Laboratory (NREL) is advancing geothermal technologies to increase renewable power production. Continuous and not dependent on weather, the geothermalresource has the potential to jump to more than 500 gigawatts in electricity production, which is equivalent to roughly half of the current U.S. capacity. Enhanced geothermal systems have a broad regional distribution in the United States, allowing the potential for development in many locations across the country.

The engineering and economic feasibility of using the geothermalresources in East Mesa, California, in a new corn processing plant is evaluated. Institutional barriers were also identified and evaluated. Several alternative plant designs which used geothermal energy were developed. A capital cost estimate and rate of return type of economic analysis were performed to evaluate each alternative. (MHR)

The objective was to consolidate and evaluate all geologic, environmental, and legal and institutional information in existing records and files, and to apply a uniform methodology to the evaluation and ranking of sites to allow the making of creditable forecasts of the supply of geothermal energy which could be available in the region over a 20 year planning horizon. A total of 1265 potentialgeothermalresource sites were identified from existing literature. Site selection was based upon the presence of thermal and mineral springs or wells and/or areas of recent volcanic activity and high heat flow. 250 sites were selected for detailed analysis. A methodology to rank the sites by energy potential, degree of developability, and cost of energy was developed. Resource developability was ranked by a method based on a weighted variable evaluation of resource favorability. Sites were ranked using an integration of values determined through the cost and developability analysis. 75 figs., 63 tabs.

Lists of publications are presented for the GeothermalResource Assessment Program for the Utah Earth Science Laboratory and the following states: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Kansas, Montana, Nebraska, Nevada, New Mexico, New York, North Dakota, Oregon, Texas, Utah, and Washington.

The following regional geological and geophysical studies are reported: establishment of a geothermal gradient data base from approximately 45,000 bottom hole temperatures recorded from well logs and interpretation of this data in terms of regional geology and establishment and interpretation of a second data base of geothermal gradients from thermal logging data from 144 holes of opportunity in the state. (MHR)

This document identifies and discusses the significant issues raised by the idea of recovering useful by-products from wastes (primarily spent brine) generated during geothermal power production. The physical availability of numerous valuable materials in geothermal brines has captured the interest of geothermalresource developers and other parties ever since their presence was known. The prospects for utilizing huge volumes of highly-saline geothermal brines for electricity generation in the Imperial Valley of California have served to maintain this interest in both private sector and government circles.

The principal goal of the program was to demonstrate economical and technical suitability of geothermal energy as a source of industrial process heat through a cooperative program with industrial firms. To accomplish that: a critical literature survey in the field was performed; a workshop with the paper and pulp industry representatives was organized; and four parallel methods dealing with technical and economical details of geothermal energy use as a source of industrial process heat were developed.

Geothermal energy comes from the internal heat of the Earth, and has been continuously exploited for the production of electricity in the United States since 1960. Currently, geothermal power is one of the ready-to-use baseload electricity generating technologies that is competing in the western United States with fossil fuel, nuclear and hydroelectric generation technologies to provide utilities and their customers with a reliable and economic source of electric power. Furthermore, the development of domestic geothermalresources, as an alternative to fossil fuel combustion technologies, has a number of associated environmental benefits. This report serves two functions. First, it provides a description of geothermal technology and a progress report on the commercial status of geothermal electric power generation. Second, it addresses the question of how much electricity might be competitively produced from the geothermalresource base. 19 figs., 15 tabs.

The GeothermalResource Areas Database (GRAD) and associated data system provide broad coverage of information on the development of geothermalresources in the United States. The system is designed to serve the information requirements of the National Progress Monitoring System. GRAD covers development from the initial exploratory phase through plant construction and operation. Emphasis is on actual facts or events rather than projections and scenarios. The selection and organization of data are based on a model of geothermal development. Subjects in GRAD include: names and addresses, leases, area descriptions, geothermal wells, power plants, direct use facilities, and environmental and regulatory aspects of development. Data collected in the various subject areas are critically evaluated, and then entered into an on-line interactive computer system. The system is publically available for retrieval and use. The background of the project, conceptual development, software development, and data collection are described here. Appendices describe the structure of the database in detail.

This paper presents the initial results of a survey of the occurrence and characteristics of geopressured fluid resources in California using the publicly- available database involving more than 150,000 oil and gas wells drilled in the State. Of the 975 documented on-shore oil and gas pools studied, about 42% were identified as potentially geopressured. Geothermal gradients in California oil and gas fields lie within the normal range of 1 F to 2 F per 100 feet. Except for the Los Angeles Basin, there was no evidence of higher temperatures or temperature gradients in geopressured pools.

A brief overview of the present day geothermal applications for hydrothermal electrical generation and direct heat use and their environmental implications is provided. Technologies and environmental impacts are considered at all points on the pathway of development resource exploration; well field, plant and transmission line construction; and plant operation. The technologies for electrical generation-direct, dry steam conversion; separated steam conversion; single-flash conversion, separated-steam/single-flash conversion and binary cycle conversion and the technologies for direct heat use - direct use of geothermal waters, surface heat exhanger, down-the hole heat exchanger and heat pump are described. A summary of the geothermal technologies planned or in operation within New Mexico geothermal areas is provided. A review of regulations that affect geothermal development and its related environmental impact in New Mexico is presented. The regulatory pathway, both state and federal, of geothermal exploration after the securing of appropriate leases, development, and construction and implementation of a geothermal facility are described. Six categories (Geophysical, Water, Air, Noise, Biota and Socioeconomics) were selected for environmental assessment. The data available is described.

The geothermalresource under Lackland Air Force Base (AFB), San Antonio, Texas was studied. It is the conclusion of the investigators that a geothermal well drilled at the site recommended by this study has a high probability of delivering geothermal fluids in sufficient quantity and at adequate temperatures to support a projected space and domestic hot water heating system. An exploratory production well location is recommended in the southwest sector of the base, based upon geologic conditions and the availability of sufficient open space to support the drilling operation. It is projected that a production well drilled at the recommended location would produce geothermal fluid of 130 to 145/sup 0/F at a rate of approximately 1000 gpm with reasonable fluid drawdowns. The Environmental Assessment for the drilling portion of the project has been completed, and no irreversible or irretrievable impacts are anticipated as a result of this drilling program. The permitting process is proceeding smoothly.

The last two decades have seen a dramatic increase in the market share of independent, nonutility generators (NUGs) relative to traditional, utility-owned generation assets. Accordingly, the ''buy versus build'' decision facing utilities--i.e., whether a utility should sign a power purchase agreement (PPA) with a NUG, or develop and own the generation capacity itself--has gained prominence in the industry. Very little of this debate, however, has focused specifically on publicly owned electric utilities, and with few exceptions, renewable sources of supply have received similarly scant attention. Contrary to historical treatment, however, the buy versus build debate is quite relevant to publicly owned utilities and renewables because publicly owned utilities are able to take advantage of some renewable energy incentives only in a ''buy'' situation, while others accrue only in a ''build'' situation. In particular, possible economic advantages of public utility ownership include: (1) the tax-free status of publicly owned utilities and the availability of low-cost debt, and (2) the renewable energy production incentive (REPI) available only to publicly owned utilities. Possible economic advantages to entering into a PPA with a NUG include: (1) the availability of federal tax credits and accelerated depreciation schedules for certain forms of NUG-owned renewable energy, and (2) the California state production incentives available to NUGs but not utilities. This article looks at a publicly owned utility's decision to buy or build new renewable energy capacity--specifically wind and geothermal power--in California. To examine the economic aspects of this decision, we used a 20-year financial cash-flow model to assess the levelized cost of electricity under four supply options: (1) public utility ownership of new geothermal capacity, (2) public utility ownership of new wind capacity, (3) a PPA for new geothermal capacity, and (4) a PPA for new wind capacity. We focus on wind and geothermal because both resources are abundant and, in some cases, potentially economic in California. Our analysis is not intended to provide precise estimates of the levelized cost of electricity from wind projects and geothermal plants; nor is our intent to compare the levelized costs of wind and geothermal power to one another. Instead, our intent is simply to compare the costs of buying wind or geothermal power to the costs of building and operating wind or geothermal capacity under various scenarios. Of course, the ultimate decision to buy or build cannot and should not rest solely on a comparison of the levelized cost of electricity. Thus, in addition to quantitative analysis, we also include a qualitative discussion of several important features of the ''buy versus build'' decision not reflected in the economic analysis.

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A case history of SUNEDCO's exploratory efforts, which ultimately led to the drilling and discovery of the Dixie Valley goethermal field, is presented. The geochemistry from three active lot springs in the area: Dixie Hot Springs, South Hot Springs, and Hyder Hot Springs, was examined. Two heat flow drilling programs were conducted at Dixie Hot Springs consisting of 45 temperature gradient holes ranging in depth from 30 to 1500 ft. From this program a heat-flow anomaly was mapped extending along the Stillwater Range front in which temperature gradients are greater than 100/sup 0/c/Km. in 1978, the number 1 SW Lamb well was drilled on a 152 acre farmout from Chevron. The well was completed as a geothermal producer in a zone of fractured volcanic rocks. Since then, five additional geothermal producing wells were completed within the anomalous area. (MJF)

This report summarizes the drilling operations and subsequent interpretation of thermal and geochemical data from the New Mexico Tech NMT-2GT (OSE RG- 05276 POD) test well. This slim hole was drilled along an elongate heat-flow anomaly at the base of the Socorro Mountains to better assess the geothermalresourcepotential (Socorro Peak geothermal system) on the western side of the New Mexico Tech campus in Socorro, New Mexico. The reservoir depth, hydraulic properties, temperature and chemistry were unknown prior to drilling. The purpose of the NMT-2GT (OSE RG-05276 POD) well was to explore the feasibility of providing geothermal fluids for a proposed district space heating system on the New Mexico Tech campus. With DOE cost over runs funds we completed NMT-2GT to a depth of 1102 feet at the Woods Tunnel drill site. Temperatures were nearly constant (41 oC ) between a depth of 400├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬ó├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?1102 feet. Above this isothermal zone, a strong temperature gradient was observed (210 oC /km) beneath the water table consistent with vertical convective heat transfer. The existence of a groundwater upflow zone was further supported by measured vertical hydraulic head measurements which varied between about 258 feet at the water table to 155 feet at a depth of 1102 feet yielding a vertical hydraulic a gradient of about 0.1. If the upflow zone is 1 km deep, then a vertical flow rate is about 0.6 m/yr could have produced the observed curvature in the thermal profile. This would suggest that the deep bedrock permeability is about 20 mD. This is much lower than the permeability measured in a specific capacity aquifer test completed in 2009 within fracture Paleozoic sandstones near the water table (3000 D). Flow rates measured during drilling were measured using a v-notch weir. Flow rates were consistently around 1000 gpm. While the temperatures are lower than we had anticipated, this geothermalresource can still be developed to heat the NM Tech campus using heat pump technology.

The US Department of Energy established a geopressured-geothermal energy program in the mid 1970`s as one response to America`s need to develop alternate energy resources in view of the increasing dependence on imported fossil fuel energy. This program continued for 17 years and approximately two hundred million dollars were expended for various types of research and well testing to thoroughly investigate this alternative energy source. This volume describes the following studies: Geopressured-geothermal hybrid cycle power plant: design, testing, and operation summary; Feasibility of hydraulic energy recovery from geopressured-geothermalresources: economic analysis of the Pelton turbine; Brine production as an exploration tool for water drive gas reservoirs; Study of supercritical Rankine cycles; Application of the geopressured-geothermalresource to pyrolytic conversion or decomposition/detoxification processes; Conclusions on wet air oxidation, pyrolytic conversion, decomposition/detoxification process; Co-location of medium to heavy oil reservoirs with geopressured-geothermalresources and the feasibility of oil recovery using geopressured-geothermal fluids; Economic analysis; Application of geopressured-geothermalresources to direct uses; Industrial consortium for the utilization of the geopressured-geothermalresource; Power generation; Industrial desalination, gas use and sales, pollutant removal, thermal EOR, sulfur frasching, oil and natural gas pipelining, coal desulfurization and preparation, lumber and concrete products kilning; Agriculture and aquaculture applications; Paper and cane sugar industries; Chemical processing; Environmental considerations for geopressured-geothermal development. 27 figs., 25 tabs.

Sumatera`s regional geologic setting has created appropriate conditions for the occurrence of wide spread, commercial geothermalresources distributed along the elongation of the island. A peculiar oblique approach of the India-Australian plate subduction beneath the Southeast Asian plate has led to island arc volcanic activity and major faulting that run along the entire island. Exploitable geothermal systems are developed beneath the volcanic complexes that are fed by shallow magma chamber and commercial viability is intensely enhanced by the presence of fault related zones of fracturing. The existence of shallow crustal magmatic heat sources and fracturing enhanced permeability provides Sumatera with the Indonesia`s largest concentration of geothermal prospects. Geological surveys of Sumatera have currently identified approximately 30 high enthalpy geothermal prospects which are mostly confined to the major zones of crustal weaknesses created by the northwest-southeast Sumatera fault system. High-temperature geothermal prospects in Sumatera are primarily associated with Quaternary andesitic to rhyotitic volcanics that emerge through this faulting system. Sumatera`s geothermalresources are typical of high-temperature hot water system with main reservoir rocks are composed of fractured Tertiary-Mesozoic sediments encountered at depth on the order of a few hundred meter to about 1,000 m overlain by low permeability layer of Quaternary volcanic rocks. The estimate on the Sumatera`s geothermalresource capability from 30 high-temperature prospects reveals a value of approximately 9,500 MW and presently, non of this capacity is commercially utilised and only less than 1% (65 MW) of this capacity, derived from two fields (Sibayak and Lempur), have been proven by exploratory drilling. The proven reserve capacity of the other field (Sarulla) in North Sumatera is still being calculated.

Domestic geothermalresources with the potential for decreasing fossil fuel use and energy cost exist at a significant number of Navy facilities. The Geothermal Plan is part of the Navy Energy R and D Program that will evaluate Navy sites and provide a technical, economic, and environmental base for subsequent resource use. One purpose of the program will be to provide for the transition of R and D funded exploratory efforts into the resource development phase. Individual Navy geothermal site projects are described as well as the organizational structure and Navy decision network. 2 figs.

Water chemistry, gas analyses, and geophysical methods including gravity and magnetic surveys, microseismic monitoring, and temperature gradient measurements were used in the Capital District area to evaluate the potential for a hydrothermal geothermal system. Water and gas chemistries provided indirect indicators, and temperature gradients provided direct indications of a geothermal system. Gravity results were supportive of gradient and chemistry data, but seismic and magnetic work have thus far provided little information on the potential system. Gradients throughout the area ranged from an average background value of about 10/sup 0/C/km to a high of roughly 44/sup 0/C/km. The highest gradient values, the most unusual water chemistries and largest carbon dioxide exhalations occur along the Saratoga and McGregor faults between Saratoga Springs and Schenectady, and indicate a good potential for a usable hydrothermal geothermal system at depth.

Computer processes geophysical well logs from central and western New York State were analyzed to evaluate the potential of subsurface formations as a source for low-temperature geothermal water. The analysis indicated that porous sandstone sections at the top of the Ordovician Theresa Formation and at the base of the Cambrian Potsdam Formation have the required depth, porosity, and permeability to act as a source for geothermal fluids over a relatively large area in the central part of the state. The fluid potential plus an advantageous geothermal gradient and the results of the test well drilled in the city of Auburn in Cayuga County suggest that low temperature geothermal energy may be a viable alternative to other more conventional forms of energy that are not indigenous to New York State.

This report is the third in a series of reports sponsored by the U.S. Department of Energy Geothermal Technologies Program in which a range of water-related issues surrounding geothermal power production are evaluated. The first report made an initial attempt at quantifying the life cycle fresh water requirements of geothermal power-generating systems and explored operational and environmental concerns related to the geochemical composition of geothermal fluids. The initial analysis of life cycle fresh water consumption of geothermal power-generating systems identified that operational water requirements consumed the vast majority of water across the life cycle. However, it relied upon limited operational water consumption data and did not account for belowground operational losses for enhanced geothermal systems (EGSs). A second report presented an initial assessment of fresh water demand for future growth in utility-scale geothermal power generation. The current analysis builds upon this work to improve life cycle fresh water consumption estimates and incorporates regional water availability into the resource assessment to improve the identification of areas where future growth in geothermal electricity generation may encounter water challenges. This report is divided into nine chapters. Chapter 1 gives the background of the project and its purpose, which is to assess the water consumption of geothermal technologies and identify areas where water availability may present a challenge to utility-scale geothermal development. Water consumption refers to the water that is withdrawn from a resource such as a river, lake, or nongeothermal aquifer that is not returned to that resource. The geothermal electricity generation technologies evaluated in this study include conventional hydrothermal flash and binary systems, as well as EGSs that rely on engineering a productive reservoir where heat exists, but where water availability or permeability may be limited. Chapter 2 describes the approach and methods for this work and identifies the four power plant scenarios evaluated: a 20-MW EGS binary plant, a 50-MW EGS binary plant, a 10-MW hydrothermal binary plant, and a 50-MW hydrothermal flash plant. The methods focus on (1) the collection of data to improve estimation of EGS stimulation volumes, aboveground operational consumption for all geothermal technologies, and belowground operational consumption for EGS; and (2) the mapping of the geothermal and water resources of the western United States to assist in the identification of potential water challenges to geothermal growth. Chapters 3 and 4 present the water requirements for the power plant life cycle. Chapter 3 presents the results of the current data collection effort, and Chapter 4 presents the normalized volume of fresh water consumed at each life cycle stage per lifetime energy output for the power plant scenarios evaluated. Over the life cycle of a geothermal power plant, from construction through 30 years of operation, the majority of water is consumed by plant operations. For the EGS binary scenarios, where dry cooling was assumed, belowground operational water loss is the greatest contributor depending upon the physical and operational conditions of the reservoir. Total life cycle water consumption requirements for air-cooled EGS binary scenarios vary between 0.22 and 1.85 gal/kWh, depending upon the extent of belowground operational water consumption. The air-cooled hydrothermal binary and flash plants experience far less fresh water consumption over the life cycle, at 0.04 gal/kWh. Fresh water requirements associated with air- cooled binary operations are primarily from aboveground water needs, including dust control, maintenance, and domestic use. Although wet-cooled hydrothermal flash systems require water for cooling, these plants generally rely upon the geofluid, fluid from the geothermal reservoir, which typically has high salinity and total dissolved solids concentration and is much warmer than normal groundwater sources, for their cooling water needs; thus,

A variable phase turbine assembly will be designed and manufactured having a turbine, operable with transcritical, two-phase or vapor flow, and a generator ľ on the same shaft supported by process lubricated bearings. The assembly will be hermetically sealed and the generator cooled by the refrigerant. A compact plate-fin heat exchanger or tube and shell heat exchanger will be used to transfer heat from the geothermal fluid to the refrigerant. The demonstration turbine will be operated separately with two-phase flow and with vapor flow to demonstrate performance and applicability to the entire range of low temperature geothermalresources. The vapor leaving the turbine is condensed in a plate-fin refrigerant condenser. The heat exchanger, variable phase turbine assembly and condenser are all mounted on single skids to enable factory assembly and checkout and minimize installation costs. The system will be demonstrated using low temperature (237F) well flow from an existing large geothermal field. The net power generated, 1 megawatt, will be fed into the existing power system at the demonstration site. The system will demonstrate reliable generation of inexpensive power from low temperature resources. The system will be designed for mass manufacturing and factory assembly and should cost less than $1,200/kWe installed, when manufactured in large quantities. The estimated cost of power for 300F resources is predicted to be less than 5 cents/kWh. This should enable a substantial increase in power generated from low temperature geothermalresources.

Technical and economic issues related to the commercial feasibility of hot dry rock geothermal energy for producing electricity and heat are discussed. Topics covered include resource characteristics, reservoir thermal capacity and lifetime, drilling and surface plant costs, financial risk and anticipated rate of return. The current status of research and deveopment efforts in the US are also summarized.

Because most sedimentary basins have been explored for oil and gas, well logs, temperatures at depth, and reservoir properties such as depth to basement and formation thickness are well known. The availability of this data reduces exploration risk and allows development of geologic exploration models for each basin. This study estimates the magnitude of recoverable geothermal energy from 15 major known U.S. sedimentary basins and ranks these basins relative to their potential. The total available thermal resource for each basin was estimated using the volumetric heat-in-place method originally proposed by (Muffler, 1979). A qualitative recovery factor was determined for each basin based on data on flow volume, hydrothermal recharge, and vertical and horizontal permeability. Total sedimentary thickness maps, stratigraphic columns, cross sections, and temperature gradient information was gathered for each basin from published articles, USGS reports, and state geological survey reports. When published data were insufficient, thermal gradients and reservoir properties were derived from oil and gas well logs obtained on oil and gas commission databases. Basin stratigraphy, structural history, and groundwater circulation patterns were studied in order to develop a model that estimates resource size, temperature distribution, and a probable quantitative recovery factor.

This study estimates the magnitude of geothermal energy from fifteen major known US sedimentary basins and ranks these basins relative to their potential. Because most sedimentary basins have been explored for oil and gas, well logs, temperatures at depth, and reservoir properties are known. This reduces exploration risk and allows development of geologic exploration models for each basin as well as a relative assessment of geologic risk elements for each play. The total available thermal resource for each basin was estimated using the volumetric heat-in-place method originally proposed by Muffler (USGS). Total sedimentary thickness maps, stratigraphic columns, cross sections, and temperature gradient Information were gathered for each basin from published articles, USGS reports, and state geological survey reports. When published data was insufficient, thermal gradients and reservoir properties were derived from oil and gas well logs obtained on oil and gas commission websites. Basin stratigraphy, structural history, and groundwater circulation patterns were studied in order to develop a model that estimates resource size and temperature distribution, and to qualitatively assess reservoir productivity.

This U.S. Department of Energy Geothermal Program Review starts with two interesting pieces on industries outlook about market conditions. Dr. Allan Jelacics introductory talk includes the statistics on the impacts of the Industry Coupled Drilling Program (late-1970's) on geothermal power projects in Nevada and Utah (about 140 MWe of power stimulated). Most of the papers in these Proceedings are in a technical report format, with results. Sessions included: Exploration, The Geysers, Reservoir Engineering, Drilling, Energy Conversion (including demonstration of a BiPhase Turbine Separator), Energy Partnerships (including the Lake County effluent pipeline to The Geysers), and Technology Transfer (Biochemical processing of brines, modeling of chemistry, HDR, the OIT low-temperature assessment of collocation of resources with population, and geothermal heat pumps). There were no industry reviews at this meeting.

The feasibility of utilizing geothermal energy at a selected plant in New York State was studied. Existing oil and gas records suggests that geothermal fluid is available in the target area and based on this potential. Friendship Dairies, Inc., Friendship, NY, was selected as a potential user of geothermal energy. Currently natural gas and electricity are used as its primary energy sources. Six geothermal system configurations were analyzed based on replacement of gas or oil-fired systems for producing process heat. Each system was evaluated in terms of Internal Rate of Return on Investment (IRR), and simple payback. Six system configurations and two replaced fuels, representative of a range of situations found in the state, are analyzed. Based on the potentialgeothermal reserves at Friendship, each of the six system configurations are shown to be economically viable, compared to continued gas or oil-firing. The Computed IRR's are all far in excess of projected average interest rates for long term borrowings: approximately 15% for guarantee backed loans or as high as 20% for conventional financing. IRR is computed based on the total investment (equity plus debt) and cash flows before financing costs, i.e., before interest expense, but after the tax benefit of the interest deduction. The base case application for the Friendship analysis is case B/20 yr-gas which produces an IRR of 28.5% and payback of 3.4 years. Even better returns could be realized in the cases of oil-avoidance and where greater use of geothermal energy can be made as shown in the other cases considered.

The environmental and socio-economic settings of four environmentally representative Gulf Coast geopressured geothermal fairways were inventoried. Subsidence predictions were prepared using feasible development scenarios for the four representative subsidence sites. Based on the results of the subsidence estimates, an assessment of the associated potential environmental and socioeconomic impacts was prepared. An inventory of mitigation measures was also compiled. Results of the subsidence estimates and impact assessments are presented, as well as conclusions as to what are the major uncertainties, problems, and issues concerning the future study of geopressured geothermal subsidence.

The objectives of the geothermal program have been to develop and apply geological and geophysical targeting procedures for the discovery of low-temperature geothermalresources related to heat-producing granite. Separate abstracts have been prepared for individual papers comprising the report. (ACR)

In 1979 a program was initiated to fully define the geothermal conditions of an area east of Canon City, bounded by the mountains on the north and west, the Arkansas River on the south and Colorado Highway 115 on the east. Within this area are a number of thermal springs and wells in two distinct groups. The eastern group consists of 5 thermal artesian wells located within one mile of Colorado Highway 115 from Penrose on the north to the Arkansas river on the south. The western group, located in and adjacent to Canon City, consists of one thermal spring on the south bank of the Arkansas River on the west side of Canon City, a thermal well in the northeast corner of Canon City, another well along the banks of Four Mile Creek east of Canon City and a well north of Canon City on Four Mile Creek. All the thermal waters in the Canon City Embayment, of which the study area is part of, are found in the study area. The thermal waters unlike the cold ground waters of the Canon City Embayment, are a calcium-bicarbonate type and range in temperature from 79 F (26 C) to a high of 108 F (42 C). The total combined surface discharge o fall the thermal water in the study area is in excess of 532 acre feet (A.F.) per year.

Generic well models have been constructed for eight major geothermalresource areas. The models define representative times and costs associated with the individual operations that can be expected during drilling and completion of geothermal wells. They were made for and have been used to evaluate the impacts of potential new technologies. Their nature, their construction, and their validation are discussed.

Carlo Simulation results, these eleven fields have 453 MWe of power generation potential and 13 876 MWt and encouraging the installation of power generating plant are underway. New geothermal legislation calls of geothermalresources and geothermal power production potential. As a first step, the geothermal inventory

Geothermal Progress Monitor Report No. 6 presents a state-by-state summary of the status of geothermal leasing, exploration, and development in major physiographic regions where geothermalresourcepotential has been identified. Recent state-specific activities are reported at the end of each state status report, while recent activities of a more general nature are summarized briefly in Part II of the report. A list of recent publications of potential interest to the geothermal community and a directory of contributors to the geothermal progress monitoring system are also included.

The City of Burbank and the Ralph M. Parsons Company studies showed several advantages for hybrid geothermal/coal fired power plants, as follows: (1) the estimated cost of producing electricity in hybrid plant is about 18.3 mills/kWh, compared to 19.3 mills/kWh in an all-coal fired power plant; (2) the coal requirements for a given plant can be reduced about 12 to 17%; and (3) the geothermal brines can be used for power plant cooling water, and in some cases, as boiler feedwater. The pertinent results of the City of Burbank studies are summarized and applied to the geothermal and coal resources of Arizona for possible future utilization.

EXPERIMENTAL VERIFICATION OF THE LOAD-FOLLOWING POTENTIAL OF A HOT DRY ROCK GEOTHERMAL RESERVOIR. The objective of this cyclic load-following experiment was to investigate the performance of the reservoir, this series of cyclic flow tests is referred to as the Load-Following Experiment, with the objective

The invertebrate surveys reported here were carried out as part of ecological studies funded by the Department of Energy in support of their environmental impact statement (EIS) for the Hawaii Geothermal Project. Currently, preparation of the EIS has been suspended, and all supporting information is being archived and made available to the public. The invertebrate surveys reported here assessed diversity and abundance of the arthropod and gastropod fauna in forested habitat and lava tubes in or near the three geothermalresource subzones. Recommendations for conservation of these organisms are given in this report. Surveys were conducted along three 100-m transect lines at each of the six forested locations. Malaise traps, baited pitfall traps, yellow pan traps, baited sponge lures, and visual examination of vegetation were used to assess invertebrate diversity along each transect line. Three of these locations were adjacent to roads, and three were adjacent to lava flows. Two of these lava-forest locations (Keauohana Forest Reserve and Pu`u O`o) were relatively remote from direct human impacts. The third location (Southeast Kula) was near a low-density residential area. Two lava tubes were surveyed. The forest over one of these tubes (Keokea tube) had recently been burned away. This tube was used to assess the effects of loss of forest habitat on the subterranean fauna. An undisturbed tube (Pahoa tube) was used as a control. Recommendations offered in this report direct geothermal development away from areas of high endemic diversity and abundance, and toward areas where natural Hawaiian biotic communities have already been greatly disturbed. These disturbed areas are mainly found in the lower half of the Kamaili (middle) geothermal subzone and throughout most of the Kapoho (lower) geothermal subzone. These recommendation may also generally apply to other development projects in the Puna District.

An overall treatment of direct geothermal applications is presented with an emphasis on the above-ground engineering. The types of geothermalresources and their general extent in the US are described. The potential market that may be served with geothermal energy is considered briefly. The evaluation considerations, special design aspects, and application approaches for geothermal energy use in each of the applications are considered. The present applications in the US are summarized and a bibliography of recent studies and applications is provided. (MHR)

The regulatory aspects of a wide range of potential projects and sequences within the projects are covered, such as: exploration, demonstration, construction, commercialization, and operation. Such topics as environmental studies, water rights, district heating, taxation archaeological clearances, and construction permits are addressed. Other general information is provided which may assist a prospective geothermal developer in understanding which state and local agencies have review responsibilities, their review procedures, and the appropriate time frame necessary to complete their review process. (MHR)

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geothermal energy exploration and development are most important. Geothermalresources in Costa Rica have of energy development in Costa Rica. The Miravalles geothermCALCIUM CARBONATE DEPOSITION IN GEOTHERMAL WELLBORES MIRAVALLES GEOTHERMAL FIELD COSTA RICA

Task 1 of the Hawaii Geothermal Project Interagency Agreement between the Fish and Wildlife Service and the Department of Energy-Oak Ridge National Laboratory (DOE) includes an annotated bibliography of published and unpublished documents that cover biological issues related to the lowland rain forest in Puna, adjacent areas, transmission corridors, and in the proposed Hawaii Geothermal Project (HGP). The 51 documents reviewed in this report cover the main body of biological information for these projects. The full table of contents and bibliography for each document is included along with two copies (as requested in the Interagency Agreement) of the biological sections of each document. The documents are reviewed in five main categories: (1) geothermal subzones (29 documents); (2) transmission cable routes (8 documents); (3) commercial satellite launching facility (Spaceport; 1 document); (4) manganese nodule processing facility (2 documents); (5) water resource development (1 document); and (6) ecosystem stability and introduced species (11 documents).

Under this Department of Energy (DOE) grant, A-Tech Corporation d.b.a. Applied Technology Associates (ATA), seeks to develop a seven-degree-of-freedom (7-DOF) seismic measurement tool for high-temperature geothermal applications. The Rotational-Enabled 7-DOF Seismometer includes a conventional tri-axial accelerometer, a conventional pressure sensor or hydrophone, and a tri-axial rotational sensor. The rotational sensing capability is novel, based upon ATA?s innovative research in rotational sensing technologies. The geothermal industry requires tools for high-precision seismic monitoring of crack formation associated with Enhanced Geothermal System (EGS) stimulation activity. Currently, microseismic monitoring is conducted by deploying many seismic tools at different depth levels along a ?string? within drilled observation wells. Costs per string can be hundreds of thousands of dollars. Processing data from the spatial arrays of linear seismometers allows back-projection of seismic wave states. In contrast, a Rotational-Enabled 7-DOF Seismometer would simultaneously measure p-wave velocity, s-wave velocity, and incident seismic wave direction all from a single point measurement. In addition, the Rotational-Enabled 7-DOF Seismometer will, by its nature, separate p- and s-waves into different data streams, simplifying signal processing and facilitating analysis of seismic source signatures and geological characterization. By adding measurements of three additional degrees-of-freedom at each level and leveraging the information from this new seismic observable, it is likely that an equally accurate picture of subsurface seismic activity could be garnered with fewer levels per hole. The key cost savings would come from better siting of the well due to increased information content and a decrease in the number of confirmation wells drilled, also due to the increase in information per well. Improved seismic tools may also increase knowledge, understanding, and confidence, thus removing some current blocks to feasibility and significantly increasing access to potentialgeothermal sites. During the Phase 1 effort summarized in this final report, the ATA Team modeled and built two TRL 3 proof-of-concept test units for two competing rotational sensor technologies. The two competing technologies were based on ATA?s angular rate and angular displacement measurement technologies: ? Angular rate: ATA?s Magnetohydrodynamic Angular Rate Sensor (Seismic MHD) ? Angular displacement: ATA?s Low Frequency Improved Torsional Seismometer (LFITS) In order to down-select between these two technologies and formulate a go / no go decision, the ATA Team analyzed and traded scientific performance requirements and market constraints against sensor characteristics and components, acquiring field data where possible to validate the approach and publishing results from these studies of rotational technology capability. Based on the results of Phase 1, the ATA Team finds that the Seismic MHD (SMHD) technology is the best choice for enabling rotational seismometry and significant technical potential exists for micro-seismic monitoring using a downhole 7-DOF device based on the SMHD. Recent technical papers and field data confirm the potential of rotational sensing for seismic mapping, increasing confidence that cost-reduction benefits are achievable for EGS. However, the market for geothermal rotational sensing is small and undeveloped. As a result, this report recommends modifying the Phase 2 plan to focus on prototype development aimed at partnering with early adopters within the geothermal industry and the scientific research community. The highest public benefit will come from development and deployment of a science-grade SMHD rotational seismometer engineered for geothermal downhole conditions and an integrated test tool for downhole measurements at active geothermal test sites.

The history of geothermal exploration in Hawaii is reviewed briefly. The nature and occurrences of geothermalresources are presented island by island. An overview of geothermal markets is presented. Other topies covered are: potential markets of the identified geothermal areas, well drilling technology, hydrothermal fluid transport, overland and submarine electrical transmission, community aspects of geothermal development, legal and policy issues associated with mineral and land ownership, logistics and infrastructure, legislation and permitting, land use controls, Regulation 8, Public Utilities Commission, political climate and environment, state plans, county plans, geothermal development risks, and business planning guidelines.

To satisfy the critical need for geothermal data to advance geothermal energy as a viable renewable energy contender, the U.S. Department of Energy is investing in the development of the National Geothermal Data System (NGDS). This paper outlines efforts among geothermal data providers nationwide to supply cutting edge geo-informatics. NGDS geothermal data acquisition, delivery, and methodology are discussed. In particular, this paper addresses the various types of data required to effectively assess geothermal energy potential and why simple links to existing data are insufficient. To create a platform for ready access by all geothermal stakeholders, the NGDS includes a work plan that addresses data assets and resources of interest to users, a survey of data providers, data content models, and how data will be exchanged and promoted, as well as lessons learned within the geothermal community.

Data pertaining to wells and thermal aquifers and data interpretation methods are presented. Findings from a program of field measurements of water temperatures (mainly in South-Central Texas) and an assessment of hydrologic properties of three Cretaceous aquifers (in North-Central Texas) are included. Landsat lineaments and their pertinance to the localization of low-temperature geothermalresources are emphasized. Lineament data were compared to structural and stratigraphic features along the Balcones/Ouachita trend in Central Texas to test for correlations. (MHR)

Approximately 50% of the cost of a new geothermal power plant is in the wells that must be drilled. Compared to the majority of oil and gas wells, geothermal wells are more difficult and costly to drill for several reasons. First, most U.S. geothermalresources consist of hot, hard crystalline rock formations which drill much slower than the relatively soft sedimentary formations associated with most oil and gas production. Second, high downhole temperatures can greatly shorten equipment life or preclude the use of some technologies altogether. Third, producing viable levels of electricity from geothermal fields requires the use of large diameter bores and a high degree of fluid communication, both of which increase drilling and completion costs. Optimizing fluid communication often requires creation of a directional well to intersect the best and largest number of fracture capable of producing hot geothermal fluids. Moineau motor stators made with elastomers cannot operate at geothermal temperatures, so they are limited to the upper portion of the hole. To overcome these limitations, Maurer Engineering Inc. (MEI) has developed a turbodrill that does not use elastomers and therefore can operate at geothermal temperatures. This new turbodrill uses a special gear assembly to reduce the output speed, thus allowing a larger range of bit types, especially tri-cone roller bits, which are the bits of choice for drilling hard crystalline formations. The Advanced Geothermal Turbodrill (AGT) represents a significant improvement for drilling geothermal wells and has the potential to significantly reduce drilling costs while increasing production, thereby making geothermal energy less expensive and better able to compete with fossil fuels. The final field test of the AGT will prepare the tool for successful commercialization.

The Alaska geothermal bibliography lists all publications, through 1986, that discuss any facet of geothermal energy in Alaska. In addition, selected publications about geology, geophysics, hydrology, volcanology, etc., which discuss areas where geothermalresources are located are included, though the geothermalresource itself may not be mentioned. The bibliography contains 748 entries.

Much of the northern counties (Apache, Coconino, Gila, Mohave, Navajo and Yavapai) is located in the Colorado Plateau province, a region of low geothermalpotential. Two areas that do show some potential are the Flagstaff - San Francisco Peaks area and the Springerville area. Flagstaff is rapidly becoming the manufacturing center of Arizona and will have many opportunities to use geothermal energy to satisfy part of its increasing need for energy. Using a computer simulation model, projections of geothermal energy on line as a function of time are made for both private and city-owned utility development of a resource.

A preliminary evaluation is presented of possible and probable problems that may be associated with hydrothermal development of the Valles Caldera Known GeothermalResource Area (KGRA), with specific reference to surface waters. Because of the history of geothermal development and its associated environmental impacts, this preliminary evaluation indicates the Valles Caldera KGRA will be subject to these concerns. Although the exact nature and size of any problem that may occur is not predictable, the baseline data accumulated so far have delineated existing conditions in the streams of the Valles Caldera KGRA. Continued monitoring will be necessary with the development of geothermalresources. Further studies are also needed to establish guidelines for geothermal effluents and emissions.

The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given. A technique developed by Biggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG).

Chaffee County, located in central Colorado, has immense potential for geothermal development. This report has been prepared to assist residents and developers in and outside the area to develop the hydrothermal resources of the county. Data has been collected and interpreted from numerous sources in order to introduce a general description of the area, estimate energy requirements, describe the resources and postulate a development plan. Electric power generation and direct heat application potential for the region are described.

Geothermal energy is thermal energy generated and stored in the Earth. Geothermal energy can manifest on the surface of the Earth, or near the surface of the Earth, where humankind may harness it to serve our energy needs. Geothermalresources are reservoirs of hot water that exist at varying temperatures and depths below the Earth's surface. Wells can be drilled into these underground reservoirs to tap steam and very hot water that can be brought to the surface for a variety of uses.

This project was conducted to evaluate the feasibility of using geothermal effluents for developing and maintaining waterfowl wetlands. Information in the document pertains to a seven State area the West where geothermalresources have development potential. Information is included on physiochemical characteristics of geothermal effluents; known effects of constituents in the water on a wetland ecosystem and water quality criteria for maintaining a viable wetland; potential of sites for wetland development and disposal of effluent water from geothermal facilities; methods of disposal of effluents, including advantages of each method and associated costs; legal and institutional constraints which could affect geothermal wetland development; potential problems associated with depletion of geothermalresources and subsidence of wetland areas; potential interference (adverse and beneficial) of wetlands with ground water; special considerations for wetlands requirements including size, flows, and potential water usage; and final conclusions and recommendations for suitable sites for developing demonstration wetlands.

Incorporates the results of flow tests for geothermal production and injection wells in the Raft River geothermal field in southern Idaho. Interference testing was also accomplished across the wellfield.

This report summarizes the results of Phase I work for a go/no go decision on Phase II funding. In the first objective, we assessed the extent to which fluid-mineral equilibria controlled deep water compositions in geothermal systems across the Great Basin. Six systems were evaluated: Beowawe; Desert Peak; Dixie Valley; Mammoth; Raft River; Roosevelt. These represent a geographic spread of geothermalresources, in different geological settings and with a wide range of fluid compositions. The results were used for calibration/reformulation of chemical geothermometers that reflect the reservoir temperatures in producing reservoirs. In the second objective, we developed a reactive -transport model of the Desert Peak hydrothermal system to evaluate the processes that affect reservoir fluid geochemistry and its effect on solute geothermometry. This included testing geothermometry on ôreactedö thermal water originating from different lithologies and from near-surface locations where the temperature is known from the simulation. The integrated multi-component geothermometer (GeoT, relying on computed mineral saturation indices) was tested against the model results and also on the systems studied in the first objective.

An estimate of the total and recoverable geopressured geothermalresource of the fairways in the Wilcox and Frio formations is made using the current data available. The flow rate of water and methane for wells located in the geopressured geothermal fairways is simulated over a 20-year period utilizing the TOUGH2 Reservoir Simulator and research data. The model incorporates relative permeability, capillary pressure, rock compressibility, and leakage from the bounding shale layers. The simulations show that permeability, porosity, pressure, sandstone thickness, well spacing, and gas saturation in the sandstone have a significant impact on the percent of energy recovered. The results also predict lower average well production flow rates and a significantly higher production of natural gas relative to water than in previous studies done from 1975 to 1980. Previous studies underestimate the amount of methane produced with hot brine. Based on the work completed in this study, multiphase flow processes and reservoir boundary conditions greatly influence the total quantity of the fluid produced as well as the ratio of gas and water in the produced fluid.

Since the 2009 American Recovery and Reinvestment Act the U.S. Department of Energyĺs Geothermal Technologies Office has funded $33.7 million for multiple data digitization and aggregation projects focused on making vast amounts of geothermal relevant data available to industry for advancing geothermal exploration. These projects are collectively part of the National Geothermal Data System (NGDS), a distributed, networked system for maintaining, sharing, and accessing data in an effort to lower the levelized cost of electricity (LCOE). Determining ôwho ownsö and ôwho maintainsö the NGDS and its data nodes (repositories in the distributed system) is yet to be determined. However, the invest- ment in building and populating the NGDS has been substantial, both in terms of dollars and time; it is critical that this investment be protected by ensuring sustainability of the data, the software and systems, and the accessibility of the data. Only then, will the benefits be fully realized. To keep this operational system sustainable will require four core elements: continued serving of data and applications; maintenance of system operations; a governance structure; and an effective business model. Each of these presents a number of challenges. Data being added to the NGDS are not strictly geothermal but data considered relevant to geothermal exploration and develop- ment, including vast amounts of oil and gas and groundwater wells, among other data. These are relevant to a broader base of users. By diversifying the client base to other users and other fields, the cost of maintaining core infrastructure can be spread across an array of stakeholders and clients. It is presumed that NGDS will continue to provide free and open access to its data resources. The next-phase NGDS operation should be structured to eventually pursue revenue streams to help off-set sustainability expenses as necessary and appropriate, potentially including income from: grants and contracts (agencies, foundations, pri- vate sector), membership, fees for services (consulting, training, customization, Ĺappĺ development), repository services (data, services, apps, models, documents, multimedia), advertisements, fees for premier services or applications, subscriptions to value added services, licenses, contributions and donations, endow- ments, and sponsorships.

These appendices include: a folio of maps showing lineaments perceived across the state; an index and critique of the Landsat images used in perceiving the lineaments; a selected bibliography on lineaments; and a discussion of area-specific assessments of geothermalresources near military bases in Bexar, Travis, and Val Verde Counties. (MHR)

An overview of the literature is presented. This is followed by a statement of some elementary electromagnetic theory necessary to establish the MKS system of units and the fundamental physics governing electrical methods of exploration. Next there is presented a reasonably detailed discussion of the electrical properties of earth materials including normal mode of conduction, surface conduction, electrode polarization, membrane polarization, semiconduction, melt conduction, real and complex resistivity, and the origin of self-potentials in geothermal systems. To illustrate how electrical methods are used within the framework of integrated geological, geochemical, and geophysical exploration, the case history of the Monroe-Red Hill hot springs system is presented.

The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. The regional piezometric surface and stratigraphic units dip towards the southwest. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given in table 2. Some of the BHT data in table 2 may vary from those previously reported by WSU. These discrepancies are the result of changes in the calibration method of the FT tool. A technique developed by Giggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG). Well data groups were selected on the premises of geographic proximity, position within the regional groundwater flow system, land slope azimuth, and land slope dip. Some data points have been excluded from the linear regression analysis on the basis of factors such as duplicate logging of the same hole, down-hole flow, holes not logged to total depth, and questionable FT tool responses.

The U.S. Department of Energy's (DOE) Geothermal Technologies Newsletter features the latest information about its geothermal research and development efforts. The GeothermalResources Council (GRC)Ś a tax-exempt, non-profit, geothermal educational association Ś publishes quarterly as an insert in its GRC Bulletin.

Utilization of geothermalresources in the town of Caliente, Nevada (population 600) has been the objective of two grants. The first grant was awarded to Ferg Wallis, part-owner and operator of the Agua Caliente Trailer Park, to assess the potential of hot geothermal water for heating the 53 trailers in his park. The results from test wells indicate sustainable temperatures of 140/sup 0/ to 160/sup 0/F. Three wells were drilled to supply all 53 trailers with domestic hot water heating, 11 trailers with space heating and hot water for the laundry from the geothermalresource. System payback in terms of energy cost-savings is estimated at less than two years. The second grant was awarded to Grover C. Dils Medical Center in Caliente to drill a geothermal well and pipe the hot water through a heat exchanger to preheat air for space heating. This geothermal preheater served to convert the existing forced air electric furnace to a booster system. It is estimated that the hospital will save an average of $5300 in electric bills per year, at the current rate of $.0275/KWH. This represents a payback of approximately two years. Subsequent studies on the geothermalresource base in Caliente and on the economics of district heating indicate that geothermal may represent the most effective supply of energy for Caliente. Two of these studies are included as appendices.

The Upper Hot Creek Ranch (UHCR) geothermal system had seen no significant exploration activity prior to initiation of this GRED III project. Geochemical geothermometers calculated from previously available but questionable quality analyses of the UHCR hot spring waters indicated possible subsurface temperatures of +320 oF. A complex Quaternary and Holocene faulting pattern associated with a six mile step over of the Hot Creek Range near the UHCR also indicated that this area was worthy of some exploration activity. Permitting activities began in Dec. 2004 for the temperature-gradient holes but took much longer than expected with all drilling permits finally being received in early August 2005. The drilling and geochemical sampling occurred in August 2005. Ten temperature gradient holes up to 500ĺ deep were initially planned but higher than anticipated drilling and permitting costs within a fixed budget reduced the number of holes to five. Four of the five holes drilled to depths of 300 to 400ĺ encountered temperatures close to the expected regional thermal background conditions. These four holes failed to find any evidence of a large thermal anomaly surrounding the UHCR hot springs. The fifth hole, located within a narrow part of Hot Creek Canyon, encountered a maximum temperature of 81 oF at a depth of 105ĺ but had cooler temperatures at greater depth. Temperature data from this hole can not be extrapolated to greater depths. Any thermal anomaly associated with the UHCR geothermal system is apparently confined to the immediate vicinity of Hot Creek Canyon where challenges such as topography, a wilderness study area, and wetlands issues will make further exploration time consuming and costly. Ten water samples were collected for chemical analysis and interpretation. Analyses of three samples of the UHCR thermal give predicted subsurface temperatures ranging from 317 to 334 oF from the Na-K-Ca, silica (quartz), and Na-Li geothermometers. The fact that all three thermometers closely agree gives the predictions added credibility. Unfortunately, the final result of this exploration is that a moderate temperature geothermalresource has been clearly identified but it appears to be restricted to a relatively small area that would be difficult to develop.

The ?Geothermal Outreach and Project Financing? project substantially added to the understanding of geothermalresources, technology, and small business development by both the general public as well as those in the geothermal community.

The Geothermal research Program of the US Department of Energy (DOE) has as one of its goals to reduce the cost of drilling geothermal wells by 25 percent. To attain this goal, DOE continuously evaluates new technologies to determine their potential in contributing to the Program. One such technology is artifical intelligence (AI), a branch of computer science that, in recent years, has begun to impact the marketplace in a number of fields. Expert systems techniques can (and in some cases, already have) been applied to develop computer-based ''advisors'' to assist drilling personnel in areas such as designing mud systems, casing plans, and cement programs, optimizing drill bit selection and bottom hole asssembly (BHA) design, and alleviating lost circulation, stuck pipe, fishing, and cement problems. Intelligent machines with sensor and/or robotic directly linked to AI systems, have potential applications in areas of bit control, rig hydraulics, pipe handling, and pipe inspection. Using a well costing spreadsheet, the potential savings that could be attributed to each of these systems was calculated for three base cases: a dry steam well at The Geysers, a medium-depth Imerial Valley well, and a deep Imperial Valley well. Based on the average potential savings to be realized, expert systems for handling lost circulations problems and for BHA design are the most likely to produce significant results. Automated bit control and rig hydraulics also exhibit high potential savings, but these savings are extremely sensitive to the assumptions of improved drilling efficiency and the cost of these sytems at the rig. 50 refs., 19 figs., 17 tabs.

This paper presents the initial results of a survey of the occurrence and characteristics of geopressured fluid resources in California using the publicly-available database involving more than 150,000 oil and gas wells drilled in the State. Of the 975 documented on-shore oil and gas pools studied, about 42% were identified as potentially geopressured. Geothermal gradients in California oil and gas fields lie within the normal range of 1░F to 2░F per 100 feet. Except for the Los Angeles Basin, there was no evidence of higher temperatures or temperature gradients in geopressured pools. The porosity of geopressured pools shows the same normal distribution as for normal pressured pools, with a mode in the range of 20 to 25%. The salinity distribution of both the geopressured and normal pressured pools appear to be bimodal, each with two peak ranges of 0 to 10,000 and 25,000 to 30,000 ppm. Compared to the U.S. Gulf Coast region, geopressured pools in California display much lower water salinities, and therefore, should have a higher solubility for methane. Geopressured pools in California occur in the depth range of less than 1,000 feet to more than 18,000 feet. The modal depth of geopressured pools in California is 2,000 to 4,000 feet, much shallower than that encountered in the Gulf Coast region. The distribution of thickness of geopressured pools is similar to that of normal pressured pools, the majority being less than 250 feet thick. The distributions of the volume of geopressured and normal pressured pools are similar, the modal value being in the range of I to 10 billion cubic feet.

This study concludes that direct use technologies, especially desalinated water production, can contribute significantly to the value added process and the overall economic viability in developing a geopressured resource. Although agriculture and aquaculture applications are marginal projects when they are the only use of a geopressured well, the small margin of profitability can contribute to improving the overall economics of the direct use development. The added complexity from a technical and management aspect may add to the overall risk and unpredictability of the project. Six combination of direct uses received economic evaluation that resulted in 15% discounted payback periods ranging from 4 to over 10 years. Many other combinations are possible depending on the resource and market variables. Selection of appropriate technologies and sizes of applications will be established by the developer that engages in geopressured resource utilization. Currently, many areas of the country where geopressured resources are located also have surplus electrical capacity and generation, thus power utilities have been selling power for less than 2 cents per kWH, well below a reasonable breakeven value for geopressured produced electricity. However, when the energy demand of the integrated geopressured facility is large enough to install power generation equipment, operating expenses can be reduced by not paying the 10 to 12 cents per kWH utility rate. The study includes an analysis of a geothermal turbine unit installed with a desalination and an agriculture/aquaculture facility, taking advantage of the cascading energy values. Results suggest that this scenario becomes profitable only where the market price for electricity exceeds five cents per kWH.

Earth Power Resources, Inc. recently completed a combined rotary/core hole to a depth of 3,813 feet at it's Hot Sulphur Springs Tuscarora Geothermal Power Project Lease Area located 70-miles north of Elko, Nevada. Previous geothermal exploration data were combined with geologic mapping and newly acquired seismic-reflection data to identify a northerly tending horst-graben structure approximately 2,000 feet wide by at least 6,000 feet long with up to 1,700 feet of vertical offset. The well (HSS-2) was successfully drilled through a shallow thick sequence of altered Tertiary Volcanic where previous exploration wells had severe hole-caving problems. The ''tight-hole'' drilling problems were reduced using drilling fluids consisting of Polymer-based mud mixed with 2% Potassium Chloride (KCl) to reduce Smectite-type clay swelling problems. Core from the 330 F fractured geothermal reservoir system at depths of 2,950 feet indicated 30% Smectite type clays existed in a fault-gouge zone where total loss of circulation occurred during coring. Smectite-type clays are not typically expected at temperatures above 300 F. The fracture zone at 2,950 feet exhibited a skin-damage during injection testing suggesting that the drilling fluids may have caused clay swelling and subsequent geothermal reservoir formation damage. The recent well drilling experiences indicate that drilling problems in the shallow clays at Hot Sulphur Springs can be reduced. In addition, average penetration rates through the caprock system can be on the order of 25 to 35 feet per hour. This information has greatly reduced the original estimated well costs that were based on previous exploration drilling efforts. Successful production formation drilling will depend on finding drilling fluids that will not cause formation damage in the Smectite-rich fractured geothermal reservoir system. Information obtained at Hot Sulphur Springs may apply to other geothermal systems developed in volcanic settings.

To study the low temperature and Hot Dry Rock (HDR) geothermalpotential of west-central New Mexico, 46 water samples were collected and geothermal gradient measurements were made in 29 wells. Water chemistry data indicate that all the samples collected are meteoric waters. High temperatures of samples taken from wells between Gallup and Tohatchi indicate these wells may derive water from a warm aquifer below the depth of the wells. The chemistries of the samples farther south on the Zuni Indian reservation suggest these waters are not circulating below 600 m of the surface. Geothermometry calculations support the conclusion that the waters sampled are meteoric. The geothermometry also indicates that the deep reservoir between Gallup and Tohatchi may be greater than 60/sup 0/C. Thermal gradient data indicate an area of high gradient on the Zuni Indian Reservation with a measured maximum of 67/sup 0/C/km between 181 m and 284 m. This high probably is not hydrologically controlled. The maximum gradients in the study area are 76/sup 0/C/km and 138/sup 0/C/km, measured just east of Springerville, Arizona. These gradients are undoubtedly controlled by circulating water, possibly heated by a magmatic source at depth and circulating back to the surface.

The NGDS released version 1 of the system on April 30, 2014 using the US Geoscience Information Network (USGIN) as its data integration platform. NGDS supports the 2013 Open Data Policy, and as such, the launch was featured at the 2014 Energy Datapalooza. Currently, the NGDS features a comprehensive user interface for searching and accessing nearly 41,000 documents and more than 9 million data points shared by scores of data providers across the U.S. The NGDS supports distributed data sharing, permitting the data owners to maintain the raw data that is made available to the consumer. Researchers and industry have been utilizing the NGDS as a mechanism for promoting geothermal development across the country, from hydrothermal to ground source heat pump applications. Case studies in geothermal research and exploration from across the country are highlighted.

scientists working in the geothermal, mining, petroleum and other industries must address. We present a brief been further related to geomechanical parameters such as changes of injection pressure, injected volume. Engineered Geothermal Systems (EGS) have the potential to expand clean renewable, baseload energy beyond

This project entails finding and assessing geothermal systems to: Increase geothermal development through research and outreach; Reduce risk in drill target selection, thus reducing project development costs; and Recent research includes development of shallow temperature surveys, seismic methods, aerial photography, field structural geology.

The nature of goethermal resources in Nevada and resource applications are discussed. The social and economic advantages of utilizing geothermal energy are outlined. Federal and State programs established to foster the development of geothermal energy are discussed. The names, addresses, and phone numbers of various organizations actively involved in research, regulation, and the development of geothermal energy are included. (MHR)

An assessment of the Steamboat Springs region in northwest Colorado was initiated and carried out in 1980 and 1981. The goal of this program was to delineate the geological features controlling the occurrence of the thermal waters (temperatures in excess of 68/sup 0/F (20/sup 0/C)) in this area at Steamboat Springs and 8 miles (12.8 km) north at Routt Hot Springs. Thermal waters from Heart Spring, the only developed thermal water source in the study area, are used in the municipal swimming pool in Steamboat Springs. The assessment program was a fully integrated program consisting of: dipole-dipole, Audio-magnetotelluric, telluric, self potential and gravity geophysical surveys, soil mercury and soil helium geochemical surveys; shallow temperature measurements; and prepartion of geological maps. The investigation showed that all the thermal springs appear to be fault controlled. Based on the chemical composition of the thermal waters it appears that Heart Spring in Steamboat Springs is hydrologically related to the Routt Hot Springs. This relationship was further confirmed when it was reported that thermal waters were encountered during the construction of the new high school in Strawberry Park on the north side of Steamboat Springs. In addition, residents stated that Strawberry Park appears to be warmer than the surrounding country side. Geological mapping has determined that a major fault extends from the Routt Hot Springs area into Strawberry Park.

The report consists of four sections dealing with progress in evaluating geologic, geochemical, and geophysical aspects of geopressured-geothermal energy resources in Louisiana. Separate abstracts have been prepared for the individual sections. (ACR)

Fining Large Aperture Fractures in GeothermalResource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis presentation at the April 2013 peer review meeting held in Denver, Colorado.

The feasibility of geothermal energy use at naval installations in Norfolk, VA, Jacksonville, FL, and Charleston, SC was assessed. Geophysical and geological studies of the above areas were performed. Engineering and economic factors, affecting potential energy use, were evaluated. The Norfolk and Jacksonville facilities are identified as candidates for geothermal systems. System costs are predicted. Economic benefits of the proposed geothermal systems are forecast, using the net present value method of predicting future income.

The Application for Certification for the construction of a 55 MW geothermal power plant and related facilities in Lake County was approved subject to terms identified in the Final Decision. The following are covered: findings on compliance with statutory site-certification requirements; final environmental impact report; procedural steps; evidentiary bases; need, environmental resources; public health and safety; plant and site safety and reliability; socioeconomic, land use, and cultural concerns, and transmission tap line. (MHR)

This document includes discussions about geothermal energy, its applications, and how it is found and developed. It identifies known geothermalresources located in Western's power marketing area, and covers the use of geothermal energy for both electric power generation and direct applications. Economic, institutional, environmental, and other factors are discussed, and the benefits of the geothermal energy resource are described.

Small businesses are the cornerstone of the American economy. Over 22 million small businesses account for approximately 99% of employers, employ about half of the private sector workforce, and are responsible for about two-thirds of net new jobs. Many small businesses fared better than the Fortune 500 in 2001. Non-farm proprietors income rose 2.4% in 2001 while corporate profits declined 7.2%. Yet not all is rosy for small businesses, particularly new ones. One-third close within two years of opening. From 1989 to 1992, almost half closed within four years; only 39.5% were still open after six years. Why do some new businesses thrive and some fail? What helps a new business succeed? Industry knowledge, business and financial planning, and good management. Small geothermal businesses are no different. Low- and medium-temperature geothermalresources exist throughout the western United States, the majority not yet tapped. A recent survey of ten western states identified more than 9,000 thermal wells and springs, over 900 low- to moderate-temperature geothermalresource areas, and hundreds of direct-use sites. Many opportunities exist for geothermal entrepreneurs to develop many of these sites into thriving small businesses. The ''Geothermal Small Business Workbook'' (''Workbook'') was written to give geothermal entrepreneurs, small businesses, and developers the tools they need to understand geothermal applications--both direct use and small-scale power generation--and to write a business and financing plan. The Workbook will: Provide background, market, and regulatory data for direct use and small-scale (< 1 megawatt) power generation geothermal projects; Refer you to several sources of useful information including owners of existing geothermal businesses, trade associations, and other organizations; Break down the complicated and sometimes tedious process of writing a business plan into five easy steps; Lead you--the geothermal entrepreneur, small company, or project developer--step-by-step through the process needed to structure a business and financing plan for a small geothermal project; and Help you develop a financing plan that can be adapted and taken to potential financing sources. The Workbook will not: Substitute for financial advice; Overcome the high exploration, development, and financing costs associated with smaller geothermal projects; Remedy the lack of financing for the exploration stage of a geothermal project; or Solve financing problems that are not related to the economic soundness of your project or are caused by things outside of your control.

The Potential Wind Power Resource in Australia: A New Perspective* Willow Hallgren, Udaya Bhaskar: globalchange@mit.edu Website: http://globalchange.mit.edu/ #12;The Potential Wind Power Resource in Australia density, and analyzes the variation of these characteristics with current and potential wind turbine hub

The Potential Wind Power Resource in Australia: A New Perspective Willow Hallgren, Udaya Bhaskar;1 The Potential Wind Power Resource in Australia: A New Perspective Willow Hallgren* , Udaya Bhaskar Gunturu intermittency can potentially be mitigated by the aggregation of geographically dispersed wind farms. Our

This paper documents the approach used to update the U.S. geothermal supply curve. The analysis undertaken in this study estimates the supply of electricity generation potential from geothermalresources in the United States and the levelized cost of electricity (LCOE), capital costs, and operating and maintenance costs associated with developing these geothermalresources. Supply curves were developed for four categories of geothermalresources: identified hydrothermal (6.4 GWe), undiscovered hydrothermal (30.0 GWe), near-hydrothermal field enhanced geothermal systems (EGS) (7.0 GWe) and deep EGS (15,900 GWe). Two cases were considered: a base case and a target case. Supply curves were generated for each of the four geothermalresource categories for both cases. For both cases, hydrothermal resources dominate the lower cost range of the combined geothermal supply curve. The supply curves indicate that the reservoir performance improvements assumed in the target case could significantly lower EGS costs and greatly increase EGS deployment over the base case.

The effects of various financial incentives on potential developers of geothermal electric energy are studied and the impact of timing of plant construction costs on geothermal electricity costs is assessed. The effect of the geothermal loan guarantee program on decisions by investor-owned utilities to build geothermal electric power plants was examined. The usefulness of additional investment tax credits was studied as a method for encouraging utilities to invest in geothermal energy. The independent firms which specialize in geothermalresource development are described. The role of municipal and cooperative utilities in geothermalresource development was assessed in detail. Busbar capital costs were calculated for geothermal energy under a variety of ownerships with several assumptions about financial incentives. (MHR)

Geothermal district heating experience in the U.S. is reviewed and evaluated to explore the potential impact of utilizing this frequently undervalued renewable energy resource for space and hot water heating. Although the ...

This report is the third in a series of reports sponsored by the U.S. Department of Energy Geothermal Technologies Program in which a range of water-related issues surrounding geothermal power production are evaluated. The first report made an initial attempt at quantifying the life cycle fresh water requirements of geothermal power-generating systems and explored operational and environmental concerns related to the geochemical composition of geothermal fluids. The initial analysis of life cycle fresh water consumption of geothermal power-generating systems identified that operational water requirements consumed the vast majority of water across the life cycle. However, it relied upon limited operational water consumption data and did not account for belowground operational losses for enhanced geothermal systems (EGSs). A second report presented an initial assessment of fresh water demand for future growth in utility-scale geothermal power generation. The current analysis builds upon this work to improve life cycle fresh water consumption estimates and incorporates regional water availability into the resource assessment to improve the identification of areas where future growth in geothermal electricity generation may encounter water challenges.

This report is the third in a series of reports sponsored by the U.S. Department of Energy Geothermal Technologies Program in which a range of water-related issues surrounding geothermal power production are evaluated. The first report made an initial attempt at quantifying the life cycle fresh water requirements of geothermal power-generating systems and explored operational and environmental concerns related to the geochemical composition of geothermal fluids. The initial analysis of life cycle fresh water consumption of geothermal power-generating systems identified that operational water requirements consumed the vast majority of water across the life cycle. However, it relied upon limited operational water consumption data and did not account for belowground operational losses for enhanced geothermal systems (EGSs). A second report presented an initial assessment of fresh water demand for future growth in utility-scale geothermal power generation. The current analysis builds upon this work to improve life cycle fresh water consumption estimates and incorporates regional water availability into the resource assessment to improve the identification of areas where future growth in geothermal electricity generation may encounter water challenges.

This addendum report presents the results of the California Division of Mines and Geology (CDMG) drilling program at Calistoga, California, which was the final geothermal-resource assessment investigation performed under terms of the second year contract (1979-80) between the U.S. Department of Energy (DOE) and the CDMG under the State Coupled Program. This report is intended to supplement information presented in CDMG's technical report for the project year, ''Resource Assessment of Low- and Moderate-Temperature Geothermal Waters in Calistoga, Napa County, California''. During the investigative phase of the CDMG's Geothermal Project, over 200 well-driller's reports were obtained from the Department of Water Resources (DWR). It was hoped that the interpretation and correlation of these logs would reveal the subsurface geology of the Upper Napa Valley and also provide a check for the various geophysical surveys that were performed in the course of the study. However, these DWR driller logs proved to be inadequate due to the brief, non-technical, and erroneous descriptions contained on the logs. As a result of the lack of useable drill-hole data, and because information was desired from,deeper horizons, it became evident that drilling some exploratory holes would be necessary in order to obtain physical evidence of the stratigraphy and aquifers in the immediate Calistoga area. Pursuant to this objective, a total of twelve sites were selected--four under jurisdiction of Napa County and eight under jurisdiction of the City of Calistoga. A moratorium is currently in existence within Napa County on most geothermal drilling, and environmental and time constraints precluded CDMG from obtaining the necessary site permits within the county. However, a variance was applied for and obtained from the City of Calistoga to allow CDMG to drill within the city limits. With this areal constraint and also funding limits in mind, six drilling sites were selected on the basis of (1) proximity to areas where geophysical surveys had been performed, (2) accessibility of the site for drill rig setup, and (3) favorability for obtaining the maximum information possible concerning the geology and the resources. Necessary landowner permission and permits were secured for these sites, and actual drilling began on December 17, 1980. Drilling was terminated on February 4, 1981, with the completion of three holes that ranged in depth from 205 to 885 feet. Use of a relatively new drilling technique called the Dual Tube Method enabled the collection of precise subsurface data of a level of detail never before obtained in the Calistoga area. As a result, a totally new and unexpected picture of the geothermal reservoir conditions there has been obtained, and is outlined in this addendum report.

A thermo-economic model has been built and validated for prediction of project economics of Enhanced Geothermal Projects. The thermo-economic model calculates and iteratively optimizes the LCOE (levelized cost of electricity) for a prospective EGS (Enhanced Geothermal) site. It takes into account the local subsurface temperature gradient, the cost of drilling and reservoir creation, stimulation and power plant configuration. It calculates and optimizes the power plant configuration vs. well depth. Thus outputs from the model include optimal well depth and power plant configuration for the lowest LCOE. The main focus of this final report was to experimentally validate the thermodynamic properties that formed the basis of the thermo-economic model built in Phase 2, and thus build confidence that the predictions of the model could be used reliably for process downselection and preliminary design at a given set of geothermal (and/or waste heat) boundary conditions. The fluid and cycle downselected was based on a new proprietary fluid from a vendor in a supercritical ORC cycle at a resource condition of 200?C inlet temperature. The team devised and executed a series of experiments to prove the suitability of the new fluid in realistic ORC cycle conditions. Furthermore, the team performed a preliminary design study for a MW-scale turbo expander that would be used for a supercritical ORC cycle with this new fluid. The following summarizes the main findings in the investigative campaign that was undertaken: 1. Chemical compatibility of the new fluid with common seal/gasket/Oring materials was found to be problematic. Neoprene, Viton, and silicone materials were found to be incompatible, suffering chemical decomposition, swelling and/or compression set issues. Of the materials tested, only TEFLON was found to be compatible under actual ORC temperature and pressure conditions. 2. Thermal stability of the new fluid at 200?C and 40 bar was found to be acceptable after 399 hours of exposure?only 3% of the initial charge degraded into by products. The main degradation products being an isomer and a dimer. 3. In a comparative experiment between R245fa and the new fluid under subcritical conditions, it was found that the new fluid operated at 1 bar lower than R245fa for the same power output, which was also predicted in the Aspen HSYSY model. As a drop-in replacement fluid for R245fa, this new fluid was found to be at least as good as R245fa in terms of performance and stability. Further optimization of the subcritical cycle may lead to a significant improvement in performance for the new fluid. 4. For supercritical conditions, the experiment found a good match between the measured and model predicted state point property data and duties from the energy balance. The largest percent differences occurred with densities and evaporator duty (see Figure 78). It is therefore reasonable to conclude that the state point model was experimentally validated with a realistic ORC system. 5. The team also undertook a preliminary turbo-expander design study for a supercritical ORC cycle with the new working fluid. Variants of radial and axial turbo expander geometries went through preliminary design and rough costing. It was found that at 15MWe or higher power rating, a multi-stage axial turbine is most suitable providing the best performance and cost. However, at lower power ratings in the 5MWe range, the expander technology to be chosen depends on the application of the power block. For EGS power blocks, it is most optimal to use multi-stage axial machines. In conclusion, the predictions of the LCOE model that showed a supercritical cycle based on the new fluid to be most advantageous for geothermal power production at a resource temperature of ~ 200C have been experimentally validated. It was found that the cycle based on the new fluid is lower in LCOE and higher in net power output (for the same boundary conditions). The project, therefore has found a new optimal configuration for low temperature geothermal power production in the form of a su

Geothermal energy, defined as heat from the Earth, is a statute-recognized renewable resource. The first U.S. geothermal power plant, opened at The Geysers in California in 1960, continues to operate successfully. The United States, as the world's largest producer of geothermal electricity, generates an average of 15 billion kilowatt hours of power per year, comparable to burning close to 25 million barrels of oil or 6 million short tons of coal per year. Geothermal has a higher capacity factor (a measure of the amount of real time during which a facility is used) than many other power sources. Unlike wind and solar resources, which are more dependent upon weather fluctuations and climate changes, geothermalresources are available 24 hours a day, 7 days a week. While the carrier medium for geothermal electricity (water) must be properly managed, the source of geothermal energy, the Earth's heat, will be available indefinitely. A geothermalresource assessment shows that nine western states together have the potential to provide over 20 percent of national electricity needs. Although geothermal power plants, concentrated in the West, provide the third largest domestic source of renewable electricity after hydropower and biomass, they currently produce less than one percent of total U.S. electricity.

The sources of geothermal fluids in South Dakota are described and some of the problems that exist in utilization and materials selection are described. Methods of heat extraction and the environmental concerns that accompany geothermal fluid development are briefly described. Governmental rules, regulations and legislation are explained. The time and steps necessary to bring about the development of the geothermalresource are explained in detail. Some of the federal incentives that encourage the use of geothermal energy are summarized. (MHR)

Two geothermal investigations were completed in three Nevada locations. The regions studied were selected from areas outlined as having direct utilization potential (Trexler and others, 1979) and included the Carson-Eagle Valley, Bis Smoky Valley and Caliente. Studies were organized around the completion of a group of tasks in each area. These tasks included: geologic reconnaissance, gravity surveys, aerial photography, fluid sampling and analysis, shallow depth temperature probe surveys, soil mercury surveys, shallow electrical resistivity measurements, and temperature gradient hole drilling. Goals of the project were to provide regional information about the nature and extent of the resources and to offer a critical evaluation of the techniques employed. Results from the work in the Carson-Eagle Valley and Big Smoky Valley are presented. (MHR)

A brief overview is given of the geological characteristics of each region of the state as they relate to potentialgeothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermalresources are outlined. (MHR)

A brief overview is given of the geological characteristics of each region of the state as they relate to potentialgeothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermalresources are outlined. (MHR)

A brief overview is given of the geological characteristics of each region of the state as they relate to potentialgeothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermalresources are outlined. (MHR)

A 216 square mile area approximately 65 miles southwest of New Orleans, Louisiana, has been geologically evaluated to determine its potential for geopressured-geothermal energy production. The structural and stratigraphic analyses were made with emphasis upon the Early and Middle Miocene age sediments which lie close to and within the geopressured section. Three geopressured sands, the Robulus (43) sand, Cibicides opima sand, and Cristellaria (I) sand, are evaluated for their potential of producing geothermal energy. Two of these sands, the Robulus (43) sand and the Cibicides opima sand, meet several of the United States Department of Energy's suggested minimum requirements for a prospective geopressured-geothermal energy reservoir.

Studies of the geothermalpotential of the western arm of the Black Rock Desert in northwestern Nevada included a compilation of existing geologic data on a detailed map, a temperature survey at 1-meter depth, a thermal-scanner survey, and gravity and seismic surveys to determine basin geometry. The temperature survey showed the effects of heating at shallow depths due to rising geothermal fluids near the known hot spring areas. Lower temperatures were noted in areas of probable near-surface ground-water movement. The thermal-scanner survey verified the known geothermal areas and showed relatively high-temperature areas of standing water and ground-water discharge. The upland areas of the desert were found to be distinctly warmer than the playa area, probably due to the low thermal diffusivity of upland areas caused by low moisture content. Surface geophysical surveys indicated that the maximum thickness of valley-fill deposits in the desert is about 3200 meters. Gravity data further showed that changes in the trend of the desert axis occurred near thermal areas. 53 refs., 8 figs., 3 tabs.

This study presents an investigation of the concept of harvesting geothermal energy that remains in heavy oil reservoirs after abandonment when steamflooding is no longer economics. Substantial heat that has accumulated within reservoir rock and its...

The Fort Bidwell Indian Reservation (FBIR) is rich in renewable energy resources. Development of its geothermalresources has the potential to profoundly affect the energy and economic future of the FBIC. Geothermal energy can contribute to making the reservation energy self-sufficient and, potentially, an energy exporter. The feasibility study assessed the feasibility of installing a geothermal district heating system to provide low-cost, efficient heating of existing and planned residences, community buildings and water, using an existing geothermal well, FB-3.

Lineaments perceived on Landsat images were evaluated to provide evidence for buried structures, which, in turn, apparently control the location of geothermal anomalies. Additional well data were obtained and a new map showing faults displacing the Buda Limestone was constructed. (MHR)

The overview statement of the socio-economic effects of developing geothermal energy in the State of Hawaii is presented. The following functions are presented: (1) identification of key social and economic issues, (2) inventory of all available pertinent data, (3) analysis and assessment of available data, and (4) identification of what additional information is required for adequate assessment.

The results of sampling for SO/sub 2/, H/sub 2/S, mercury, and radon are presented and discussed. The difficulties in differentiating the effects of the well HGP-A from the background of volcanism are described. Soil and water mercury analyses as techniques for geothermal exploration are suggested. (MHR)

The Salida Geothermal Prospect (Poncha Hot Springs) was evaluated for industrial and commercial direct heat applications at Salida, Colorado, which is located approximately five miles east of Poncha Hot Springs. Chaffee Geothermal, Ltd., holds the geothermal leases on the prospect and the right-of-way for the main pipeline to Salida. The Poncha Hot Springs are located at the intersection of two major structural trends, immediately between the Upper Arkansas graben and the Sangre de Cristo uplift. Prominent east-west faulting occurs at the actual location of the hot springs. Preliminary exploration indicates that 1600 gpm of geothermal fluid as hot as 250/sup 0/F is likely to be found at around 1500 feet in depth. The prospective existing endusers were estimated to require 5.02 x 10/sup 10/ Btu per year, but the total annual amount of geothermal energy available for existing and future endusers is 28.14 x 10/sup 10/ Btu. The engineering design for the study assumed that the 1600 gpm would be fully utilized. Some users would be cascaded and the spent fluid would be cooled and discharged to nearby rivers. The economic analysis assumes that two separate businesses, the energy producer and the energy distributor, are participants in the geothermal project. The producer would be an existing limited partnership, with Chaffee Geothermal, Ltd. as one of the partners; the distributor would be a new Colorado corporation without additional income sources. Economic evaluations were performed in full for four cases: the Base Case and three alternate scenarios. Alternate 1 assumes a three-year delay in realizing full production relative to the Base Case; Alternate 2 assumes that the geothermal reservoir is of a higher quality than is assumed for the Base Case; and Alternate 3 assumes a lower quality reservoir. 11 refs., 34 figs., 40 tabs.

The U.S. Department of Energy (DOE) Geothermal Technologies Program (GTP) tasked the National Renewable Energy Laboratory (NREL) with conducting the annual geothermal supply curve update. This report documents the approach taken to identify geothermalresources, determine the electrical producing potential of these resources, and estimate the levelized cost of electricity (LCOE), capital costs, and operating and maintenance costs from these geothermalresources at present and future timeframes under various GTP funding levels. Finally, this report discusses the resulting supply curve representation and how improvements can be made to future supply curve updates.

This paper presents an assessment of global economic energy potentials for all major natural energy resources. This work is based on both an extensive literature review and calculations using natural resource assessment data. Economic potentials are presented in the form of cost-supply curves, in terms of energy flows for renewable energy sources, or fixed amounts for fossil and nuclear resources, with strong emphasis on uncertainty, using a consistent methodology that allow direct comparisons to be made. In order to interpolate through available resource assessment data and associated uncertainty, a theoretical framework and a computational methodology are given based on statistical properties of different types of resources, justified empirically by the data, and used throughout. This work aims to provide a global database for natural energy resources ready to integrate into models of energy systems, enabling to introduce at the same time uncertainty over natural resource assessments. The supplementary mate...

GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey.

Washington State's geothermalpotential is wide spread. Hot springs and five strato volcanoes existing throughout the Cascade Range, limited hot spring activity on the Olympic Peninsula, and broad reaching, low temperature geothermalresources found in the Columbia Basin comprise the extent of Washington's known geothermalresources. Determination of resource ownership is the first step in proceeding with geothermal exploration and development activities. The federal and state processes are examined from pre-lease activity through leasing and post-lease development concerns. Plans, permits, licenses, and other requirements are addressed for the federal, state, and local level. Lease, permit, and other forms for a number of geothermal exploration and development activities are included. A map of public lands and another displaying the measured geothermalresources throughout the state are provided.

The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating and cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermalresources and the exploration of the resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental consideration. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very large potential in the United States.

The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermalresources and the exploration of these resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse, aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental considerations. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very potential in the United States.

The proposed design, construction, and operation of a commercial-scale (45 MWe net) binary-cycle geothermal demonstration power plant are described using the liquid-dominated geothermalresource at Heber, Imperial County, California. The following are included in the environmental assessment: a description of the affected environment, potential environmental consequences of the proposed action, mitigation measures and monitoring plans, possible future developmental activities at the Heber anomaly, and regulations and permit requirements. (MHR)

, Stanford, California, January 31 - February 2, 2011 SGP-TR-191 GEOTHERMALRESOURCES IN THE PACIFIC ISLANDS: THE POTENTIAL OF POWER GENERATION TO BENEFIT INDIGENOUS COMMUNITIES Alex J. McCoy-West1,2 , Sarah Milicich1 their untapped geothermalresources) for cost effective power production and direct-use applications. As part

California's geographic and end-use markets which could directly use low and moderate temperature geothermalresources are ranked and described, as well as those which have the highest potential for near-term commercial development of these resources. Building on previous market surveys, the assessment determined that out of 38 geothermalresource areas with characteristics for direct use development, five areas have no perceived impediments to near-term development: Susanville, Litchfield, Ontario Hot Springs, Lake Elsinore, and the Salton Sea Geothermal Field. Twenty-nine applications were compared with previously selected criteria to determine their near-term potential for direct use of geothermal fluids. Seven categories were found to have the least impediments to development; agriculture and district heating applications are considered the highest. Ten-year projections were conducted for fossil fuel displacement from the higher rated applications. It is concluded that greenhouses have the greatest displacement of 18 x 10/sup 6/ therms per year.

Those phosphate related and food processing industries in Southeastern Idaho are identified which require large energy inputs and the potential for direct application of geothermal energy is assessed. The total energy demand is given along with that fractional demand that can be satisfied by a geothermal source of known temperature. The potential for geothermalresource development is analyzed by examining the location of known thermal springs and wells, the location of state and federal geothermal exploration leases, and the location of federal and state oil and gas leasing activity in Southeast Idaho. Information is also presented regarding the location of geothermal, oil, and gas exploration wells in Southeast Idaho. The location of state and federal phosphate mining leases is also presented. This information is presented in table and map formats to show the proximity of exploration and development activities to current food and phosphate processing facilities and phosphate mining activities. (MHR)

The purpose was to explore and develop geothermal energy resources on Indian lands. Activities included the following: (1) continued review of Indian communities and their potential for geothermal energy development; (2) introduced tribes to the availability of geothermal energy and removed the barriers to the implementation of this energy source; (3) provided information by telephone and by mailing packages of information; (4) published articles on geothermal energy development in the UIPA newsletter and supplied articles to other Indian publication; (5) conducted two seminars specific to geothermal energy development on Indian lands in western states; (6) carried out survey of Indian attitudes and opinions toward energy in general and geothermal energy in specific; (7) incorporated geothermal energy development information in Economic Development Administration sponsored tribal government management programs, and (8) developed draft written material addressing Indian planning problems and supporting their ability to affect a more productive working relationship with government agencies and reduced dependency.

The Pumpernickel Valley geothermal project area is located near the eastern edge of the Sonoma Range and is positioned within the structurally complex Winnemucca fold and thrust belt of north-central Nevada. A series of approximately north-northeast-striking faults related to the Basin and Range tectonics are superimposed on the earlier structures within the project area, and are responsible for the final overall geometry and distribution of the pre-existing structural features on the property. Two of these faults, the Pumpernickel Valley fault and Edna Mountain fault, are range-bounding and display numerous characteristics typical of strike-slip fault systems. These characteristics, when combined with geophysical data from Shore (2005), indicate the presence of a pull-apart basin, formed within the releasing bend of the Pumpernickel Valley ľ Edna Mountain fault system. A substantial body of evidence exists, in the form of available geothermal, geological and geophysical information, to suggest that the property and the pull-apart basin host a structurally controlled, extensive geothermal field. The most evident manifestations of the geothermal activity in the valley are two areas with hot springs, seepages, and wet ground/vegetation anomalies near the Pumpernickel Valley fault, which indicate that the fault focuses the fluid up-flow. There has not been any geothermal production from the Pumpernickel Valley area, but it was the focus of a limited exploration effort by Magma Power Company. In 1974, the company drilled one exploration/temperature gradient borehole east of the Pumpernickel Valley fault and recorded a thermal gradient of 160oC/km. The 1982 temperature data from five unrelated mineral exploration holes to the north of the Magma well indicated geothermal gradients in a range from 66 to 249oC/km for wells west of the fault, and ~283oC/km in a well next to the fault. In 2005, Nevada Geothermal Power Company drilled four geothermal gradient wells, PVTG-1, -2, -3, and -4, and all four encountered geothermal fluids. The holes provided valuable water geochemistry, supporting the geothermometry results obtained from the hot springs and Magma well. The temperature data gathered from all the wells clearly indicates the presence of a major plume of thermal water centered on the Pumpernickel Valley fault, and suggests that the main plume is controlled, at least in part, by flow from this fault system. The temperature data also defines the geothermalresource with gradients >100oC/km, which covers an area a minimum of 8 km2. Structural blocks, down dropped with respect to the Pumpernickel Valley fault, may define an immediate reservoir. The geothermal system almost certainly continues beyond the recently drilled holes and might be open to the east and south, whereas the heat source responsible for the temperatures associated with this plume has not been intersected and must be at a depth greater than 920 meters (depth of the deepest well ľ Magma well). The geological and structural setting and other characteristics of the Pumpernickel Valley geothermal project area are markedly similar to the portions of the nearby Dixie Valley geothermal field. These similarities include, among others, the numerous, unexposed en echelon faults and large-scale pull-apart structure, which in Dixie Valley may host part of the geothermal field. The Pumpernickel Valley project area, for the majority of which Nevada Geothermal Power Company has geothermal rights, represents a geothermal site with a potential for the discovery of a relatively high temperature reservoir suitable for electric power production. Among locations not previously identified as having high geothermalpotential, Pumpernickel Valley has been ranked as one of four sites with the highest potential for electrical power production in Nevada (Shevenell and Garside, 2003). Richards and Blackwell (2002) estimated the total heat loss and the preliminary production capacity for the entire Pumpernickel Valley geothermal system to be at 35MW. A more conservative estimate, for

This study is concerned with the estimation of the National geothermal market potential and penetration in direct heat applications for residences and certain industry segments. An important aspect of this study is that the analysis considers both known and anticipated goethermal resources. This allows for an estimation of the longer-range potential for geothermal applications. Thus the approach and results of this study provide new insights and valuable information not obtained from more limited, site-specific types of analyses. Estimates made in this study track geothermal market potential and projected penetration from the present to the year 2020. Private sector commercialization of geothermal energy over this period requires assistance in the identification of markets and market sizes, potential users, and appropriate technical applications.

Ninety-seven geothermal wells and springs were identified and plotted on a compiled geologic map of the 40-square-mile study area. These wells and springs were concentrated in three distinguishable resource areas: Arrowhead Hot Springs; South San Bernardino; and Harlem Hot Springs - in each of which detailed geophysical, geochemical, and geological surveys were conducted. The Arrowhead Hot Springs geothermal area lies just north of the City of San Bernardino in the San Bernardino Mountains astride a shear zone (offshoot of the San Andreas fault) in pre-Cambrian gneiss and schist. The Harlem Hot Springs geothermal area, on the east side of the City, and the south San Bernardino geothermal area, on the south side, have geothermal reservoirs in Quaternary alluvial material which overlies a moderately deep sedimentary basin bound on the southwest by the San Jacinto fault (a ground water barrier). Geothermometry calculations suggest that the Arrowhead Hot Springs geothermal area, with a maximum reservoir temperature of 142/sup 0/C, may have the highest maximum reservoir temperature of the three geothermal areas. The maximum temperature recorded by CDMG in the south San Bernardino geothermal area was 56/sup 0/C from an artesian well, while the maximum temperature recorded in the Harlem Hot Springs geothermal area was 49.5/sup 0/C at 174 meters (570 feet) in an abandoned water well. The geophysical and geological surveys delineated fault traces in association with all three of the designated geothermal areas.

The principal purpose of this case study of the Sumikawa Geothermal Field is to document and to evaluate the use of drilling logs, surface and downhole geophysical measurements, chemical analyses and pressure transient data for the assessment of a high temperature volcanic geothermal field. This comprehensive report describes the work accomplished during FY 1993-1996. A brief review of the geological and geophysical surveys at the Sumikawa Geothermal Field is presented (Section 2). Chemical data, consisting of analyses of steam and water from Sumikawa wells, are described and interpreted to indicate compositions and temperatures of reservoir fluids (Section 3). The drilling information and downhole pressure, temperature and spinner surveys are used to determine feedzone locations, pressures and temperatures (Section 4). Available injection and production data from both slim holes and large-diameter wells are analyzed to evaluate injectivity/productivity indices and to investigate the variation of discharge rate with borehole diameter (Section 5). New interpretations of pressure transient data from several wells are discussed (Section 6). The available data have been synthesized to formulate a conceptual model for the Sumikawa Geothermal Field (Section 7).

SGP-TR 9 * GEOTHERMAL ENERGY DEVELOPMENT Paul Kruger C i v i l Engineering Department Stanford on an aggressive program t o develop its indigenous resources of geothermal energy. For more than a decade, geothermal energy has been heralded as one of the more promising forms of energy a l t e r n a t e t o o i l

Ninety-eight geothermal wells and springs were identified and plotted, and a geologic map and cross sections were compiled. Detailed geophysical, geochemical, and geological surveys were conducted. The geological and geophysical work delineated the basement highs and trough-like depressions that can exercise control on the occurrence of the thermal waters. The Rinconada fault was also evident. Cross sections drawn from oil well logs show the sediments conforming against these basement highs and filling the depressions. It is along the locations where the sediments meet the basement highs that three natural warm springs in the area occur. Deep circulation of meteoric waters along faults seems to be a reasonable source for the warm water. The Santa Margarita, Pancho Rico, and Paso Robles Formations would be the first permeable zones that abut the faults through which water would enter. Temperatures and interpretation of well logs indicate the warmest aquifer at the base of the Paso Robles Formation. Warm water may be entering higher up in the section, but mixing with water from cooler zones seems to be evident. Geothermometry indicates reservoir temperatures could be as high as 91/sup 0/C (196/sup 0/F).

Formation of a National Geothermal Institute to develop the human resources that will be needed to transform and grow the U.S. energy infrastructure to achieve the utilization of AmericaÉs vast geothermalresource base.

The sources of geothermal fluids in South Dakota are described and some of the problems that exist in utilization and materials selection are detailed. Methods of heat extraction and the environmental concerns that accompany geothermal fluid development are briefly described. Governmental rules, regulations and legislation are explained. The time and steps necessary to bring about the development of the geothermalresources are explained in detail. Some of the federal incentives that encourage the use of geothermal energy are summarized.